Aristoklis, still not absolute proof the Gennadios Scholarios did not sign at Florence but it seems highly unlikely that he did so:
This is from an interesting short article by a Catholic monk who spent time on the Holy Mountain in 1994
THE SCHISM: GROUNDS FOR DIVISION, GROUNDS FOR UNITY
"A LATIN'S LAMENTATION OVER GENNADIOS SCHOLARIOS"
Fr. Hugh Barbour, O. Praem.
http://www.balkanstudies.org/1998/barber.htm
Dear Aristoklis,
Some more information to hand about Florence and those who signed.
Return of the Greeks Home. Rejection of the Florentine Union by the Orthodox Eastern Church.As soon as the travelers stepped on shore, the inhabitants of Constantinople assailed the Bishops with questions: "How did the Council end? Have we gained the victory?" Those, who had been forced to the union, or had joined it from interested motives, but had not as yet lost all conscience of their crime, did not conceal the truth. Feeling themselves now at liberty in their native land, amidst their orthodox brethren, they answered with heartfelt sorrow: "We have sold our faith, we have exchanged Orthodoxy for heterodoxy, and losing our former pure faith have become azymites. May our hands, which signed the unjust decree be cut off! May our tongues which have spoken consent with the Latins be plucked out!" These were the first words of the good but weak Pastors - Anthony of Heraclea, the oldest members of the Council, and others. Such news made a terrible impression on the orthodox townspeople. Everyone avoided the new arrivers, and those who had anything to do with them. The clergy who had remained in Constantinople would not even agree to officiate with those, who repenting of their consent to the union, declared that they were forced to it!
The Emperor, who had never felt a real inclination to act in the cause of the Latins, and now dissatisfied with the Pope, grieving about the loss of his wife, and troubled by the public discontent with the union, would not for a long time occupy himself with Church affairs. Three months had elapsed since the return of the Greeks, and the Church of Constantinople had still no Patriarch. At last the Emperor ordered the proper persons to think about the election of the Patriarch, an election the more necessary, as the disorders among the clergy were every day getting more and more violent. Then arose the question, "whom to elect?" Was the Patriarch to be chosen from out of those, who had shown the most zeal in the cause of the union, or from out of the defenders of Orthodoxy? The election of the Patriarch was to settle the lot of the union proclaimed in Florence. The Emperor, though little inclined to favour the Latins, would not however break his alliance with Rome. This was the reason of his not choosing Bessarion or any other zealot in the cause of the union, but demanded at the same time that the person chosen should be an upholder of the union.
The proposal of the Patriarchal throne was first made to Mark Of Ephesus, the firm defender of Orthodoxy, and on his refusal of this dignity, as must have been expected, three candidates were then chosen from out of those, who had been at the Council and signed the act of union; namely, Anthony of Heraclea, Dorotheus of Trebizond, and Metrophanes of Cyzicus. But Anthony and Dorotheus, as they rejected the union, so also did they reject the proffered honour. Anthony addressing the Council, said: "I have come here not to be elected, but to disburden my conscience before the Council, a thing I stand in need of very much. I, as you yourselves know, did not agree with those, who approved of the union, but I did sign the decree, though involuntarily. And since then has my conscience constantly smitten me. Bowed down with remorse, I have been seeking an opportunity of throwing this weight off my soul. I thank God, that He has spared me to see you all together in the assembly, and that now I can free myself of my burden by telling you all I wished to say. I repeat therefore, that I reject the union, that I find the Florentine decree contrary to the ancient tradition of the Holy Catholic Church, and give myself over to be judged by the Church, as guilty of having signed that which ought not to have been signed."
After this, Metrophanes was chosen, who at the desire of the royal officers gave a written promise of upholding the Florentine union. He ascended the Patriarchal throne on the 4th of May 1440.
Though the promise given by Metrophanes was made in secret, - though even at that time there was no mention before the Pope; the unceremonious bearing towards him of the bishop present at his ordination as the Papal representative; then, again, the disappointment of the general expectation, that the new Patriarch would put affairs into their former order; all this together served to alienate most of the orthodox from the Patriarch. Many of the bishops would not officiate together with him; and when the Emperor tried to compel them to do so, Mark of Ephesus and Anthony of Heraclea secretly left Constantinople (May 14).
After this, the Emperor began to act with still greater care, especially when his brother Demetrius, who had not received the Florentine union, availing himself of the coolness of the people to the Emperor for favouring the Latin Church, openly opposed him; so that the Pope accused John of weakness and indifference to the cause of the union, and Metrophanes positively threatened to leave his throne.
At the Emperor's persuasion, however, remaining where he was, he began to act in favour of the union, appointing his friends to the vacant dioceses; and when Demetrius again made friends with the Emperor, he urgently demanded a complete union with the Church of Rome, by right of the decree passed in Florence. But at the time when the Bishops were assembling in Constantinople, to discuss the means of bringing the plans to pass, Metrophanes died (Aug. 1, 1443). The Patriarch's death seemed to justify the severe sentence which had been pronounced over his actions in Jerusalem by the other three Patriarchs.
The Eastern Patriarchs already knew of the different Latin plans for gaining over the Greeks, from a letter written by Joseph, the Patriarch of Constantinople, either in Florence or Ferrara. After being informed by the Pope of the termination of the various discussions, they soon received an invitation from him to join the union of Churches agreed to at Florence, in which he carefully concealed the conditions under which the union took place. The Patriarchs came to know of these conditions from those who had returned from Italy. Burning with zeal for Orthodoxy, notwithstanding its persecution by the Turks, one of these pastors of the East answered the Pope, saying, that he was ready to enter into union with the Church of Rome, if that Church receives all ancient decrees of the Ecumenical Councils, and the doctrines confirmed by them and the Holy Fathers. "On this condition," he wrote, "we receive the Council of Florence, and do not refuse to mention the Pope's name in the service. In case of the contrary, we reject the Council; we sentence the bishops and clergy who receive it to be degraded from their rank, and the laymen to be excommunicated." Not satisfied with this, the same Eastern Patriarch wrote to the Emperor John 2 "If you have given way to the Latins for a time only, in hopes of receiving their aid for the empire, and do now reject their doctrine and return to the orthodox faith of your royal ancestors, then we will pray for the salvation of the empire, and especially for thy soul, that the Lord may pardon you all your sins. But if you will be obstinate, and defend a doctrine strange to our Church, then not only will we leave off remembering you in our prayers, but will sentence you to a strict epitimia, in order that the disease of the strange and dangerous doctrine should not circulate further in Christ's Church. We cannot rule the Orthodox Church as hirelings; but for Christ's and His Gospel's sake we are ready to lay down our souls, bodies, blood, all that we have here on earth."
A few months afterwards all the three Eastern Patriarchs assembled in Jerusalem; and having been informed by Arsenius, Metropolitan of Caesarea, of the Metropolitans and Bishops ordained by Metrophanes from among the Latins, pronounced judgment over the unworthy pastors, and proclaimed them deprived of all Church dignities till a Council should have examined their orthodoxy. Giving full powers to Arsenius for acting conformably with their decision throughout the whole of the East, the Patriarchs - Philotheus of Alexandria, Dorotheus of Antioch, and Joachim of Jerusalem - wrote in their patriarchal letter: "The Metropolitan of Caesarea of Cappadocia has informed us of the disorders occasioned by the lawless Council of Florence in Constantinople; a Council in which the Greeks received the Latin dogmas contrary to the ancient canons of the Orthodox Church. The same Metropolitan informed us, that Metrophanes of Cyzicum, who hath unlawfully usurped the Constantinopolitan chair, doth distribute dioceses in the Constantinopolitan Patriarchate and in all the East to his associates, who corrupt their fold by their false doctrine, and sow temptations in Christ's Church. Wherefore we, in the name of the vivifying and inseparable Trinity, do through this Council declare to all Metropolitans, Bishops, and others of the clergy ordained by Metrophanes, that they, for partaking of this heresy, are deprived of their right of officiating, of all their ecclesiastical degrees, until their faith shall be examined by the Ecumenical Council. Should they not obey our decree, and voluntarily leave their places, which they occupy unlawfully, let them then be excommunicated by the Holy and Consubstantial Trinity, both they, and those who think together with them." Giving the Metropolitan of Caesarea the right of carrying out this decree, the Patriarchs also gave him full powers to preach publicly against the unjust union, to expose and correct all the heterodox thinkers. The decree was published in April, 1443. Mark of Ephesus, the aged defender of Orthodoxy, weighed down by age and illness, but strong in spirit, was not silent also. In his circulars to all Christians, he conjured them to depart from the Florentine union, as one offensive to God; vividly representing the admixture of the old with the new, of the orthodox and patristical with what was newly invented by the Latinizing Greeks, and offered his own confession of faith on the pure doctrine of the Church. "These people," he wrote, "admit with the Latins that the Holy Ghost proceeds from the Son, and derives His existence from Him; for so says their definition, and at the same time they say with us that the Spirit proceeds from the Father. With the Latins, they think the addition made to the Creed lawful and just; and with us will not pronounce it. With them they say that azymes are the Body of Christ, and with us dare not communicate on them. Is not this sufficient to show that they came to the Latin Council, not to investigate the truth, which they once possessed and then betrayed, but simply to earn some gold, and attain a false and not a true union? False: for they read two creeds, as they did before; perform two different liturgies, one on leavened, the other on unleavened bread; two baptisms, one by the trine immersion, and the other by aspersion - one with the holy chrism, the other without it. In like manner all other customs are different with them, e. g., fasts, church rites, &c. What sort of union is this, then, when it has no external sign? How could they join together, retaining each his own? Many were tempted by the idea." Mark continued, "that one can find a medium between two doctrines. True: one can find such expressions which, having a double meaning, could at the same time express something between the two doctrines. But a doctrine midway between two contrary doctrines on the same subject is impossible; for in this case it must be something between truth and falsehood, between an affirmation and a negation. Thus, if the Latin doctrine of the Spirit's procession from the Son is just, then ours is false. What middle doctrine can there be here?" In the end of his epistle Mark wrote, "Avoid, brethren, such teachers, and all communion with them. They are false apostles, workers of evil transformed into Apostles of Christ. ... It is not the Lord Jesus they serve, but their own bellies, and seduce the hearts of the innocent by their sweet words and blessings. You know what the Apostles command us to do: `Though an angel from heaven preach any other gospel unto you than that which we have preached unto you, let him be accursed (Gal. 1:

. And Christ's beloved disciple says, "If there come any unto you, and bring not this doctrine, receive him not into your house, neither bid him God speed: for he that biddeth him God speed is partaker of his evil deeds (2 John 10-11). Keep, then, to the traditions received by you, both those which are written and not written, so as not to lose your own security by giving way to evil doctrines." So George Scholarius, who for a time inclined towards the Latins, was now confirmed by Mark in the true faith, and afterwards became one of its most zealous defenders. Without Mark of Ephesus, none of those, who had rejected the union would enter into any disputes with their opponents. Following Mark's example, his brother John Eugenicus wrote a refutation of the Florentine decree. Syropulus put all the actions of the Council in their true light; in like manner Amirutius represented, though briefly, the secret motives of the Greeks for inclining to the union with the Church of Rome. Another philosopher, Gemistes Pletho, who had defended the orthodox doctrine at the Council, also published a defense of the orthodox doctrine on the procession of the Holy Spirit.
Thus, we see, that from all sides voices were raised against the Florentine union. The Emperor however retained the same relations to the Orthodox and the Church of Rome. Brooding on his favourite idea of throwing off the Turkish yoke, he had already entered into negotiations with the Pope and Yladislaus, the King of Hungary, concerning the mutual concentration of forces against the Ottoman Empire. Their plans had been to cause a revolt against Amurath in Asia Minor, and by alluring him there with the best part of his forces, to cut off his return to Europe by means of a powerful fleet, and then retake all the towns in his European dominions. The Pope had already invited the European Monarchs to aid the unfortunate Greeks. Cardinal Caesarini persuaded Vladislaus to break a treaty of peace concluded by him a year ago with Amurath for the space of ten years. The fleet arrived in the Hellespont. But Amurath managed to return from Asia, and even to rout Vladislaus' army under Varna (Nov. 10, 1444). Vladislaus himself and Cardinal Caesarini fell in this battle. So vanished all the hopes placed in the union, which God had not blessed!
But even after this, John still could not make up his mind to break all his relations with the Pope. For about three years the Church of Constantinople had no Patriarch after the death of Metrophanes, and the vacant see was given to Gregory Mamma, the Emperor's confessor, and one of the most active causes of the Florentine union. He himself wrote objections to Mark's writings, and began a dispute in Constantinople between the principal defenders of Orthodoxy and the Latin litterati. The Pope named him for his zeal in the Latin cause, Patriarch also of the Latin party then in Constantinople. But notwithstanding all his efforts, as the Pope himself writes, he could not proclaim and enact the decree passed in Florence. So strong was the aversion of the clergy and people to the Latin union, which was attained at the sacrifice of Orthodoxy! The Bishops and clergy of Constantinople demanded, that an Ecumenical Council should be held in Constantinople itself to terminate all the evil caused by the adherents of the union. But the Emperor John died (Oct. 31, 1448) before he had time to satisfy these de-mands; at all events before his death he rejected all union with the Church of Rome. At last the innermost wishes of the orthodox pastors and people were fulfilled. A year and a half after Constantine's accession to the throne of Byzantium, three Eastern Patriarchs in whose name, though without their consent, the Florentine unorthodox "decree" was signed, viz., Philotheus of Alexandria, Dorotheus of Antioch and Theophanes of Jerusalem, assembled in Constantinople with many Metropolitans and Bishops to quiet the disturbed Church. Assembling a Council in the Church of S. Sophia in Constantinople, they deprived Gregory Mamma of his patriarchal throne and appointed the Orthodox Athanasius in his place, and then in the name of all the Eastern Church rejected the decree of the Council of Florence which they convicted as having acted contrary to the orthodox faith, and accused the Church of Rome of many digressions from the ancient rules and rites of he Church Ecumenical. Gregory soon after this left as a fugitive for Rome (August, 1451).
One could have hoped that now peace would have been quite reinstated in the Constantinopolitan Church. But Constantine wishing to save his throne, to defend which he had hardly five thousand soldiers of his own, again turned for aid to the Pope, and by this caused new disorder in the Church, which terminated with the fall of the very Empire. The new Commander of the Turks, - the harsh and ambitious Mahomet II, immediately on his accession to the throne, (Feb. 5th, 1451) - commenced planning the conquest of Constantinople. Constantine was struck with terror on hearing this, and sent off an embassy to Rome petitioning help, promising to fulfil the Florentine treaty, and even inviting Gregory to return to Constantinople.
When this became known, the defenders of Orthodoxy were sorely taken aback. George Scholarius then stood at their head (he was called Gennadius on receiving tonsure). Mark had already passed into eternity, and before his death had bequeathed to his friend the keeping of the ancient Orthodoxy. Gennadius, who then lived in the monastery of the All-possessing God, when preaching a sermon during the Emperor's visit to the monastery, tried to dissuade him from an union with the Church of Rome, which in fact was hardly of any use to Constantine. Eugenius' successor, Pope Nicholas V, sent to Constantinople, not an army and fleet, but only his Cardinal, Isidore, the ex-Metropolitan of Russia (Nov. 1452). A very short time passed in negotiations with him; but few consented to the union; only three Bishops and some of the Clergy received it; even the Emperor was not sincere in accepting it. The greater part of the Clergy, and especially the Monks, positively refused to take part in any negotiations with an apostate Greek.
Nevertheless, on the 12th of December, 1452, the spiritual and civil authorities assembled in the Church of S. Sophia. Cardinal Isidore read the act of union, (the first time after its proclamation in Florence) and in token of the reconciliation of Churches, solemnly officiated in the Liturgy together with the Greek and Latin Clergy, in which the names of Pope Nicholas and the ex-Patriarch Gregory were mentioned. But many persons present at the service would not even take the antidoron from the officiating clergy.
In the meantime, while this ceremony was going on in the Church of S. Sophia, crowds of the Orthodox made their way to the monastery in which Gennadius Scholarius was, asking him how they were to act. Gennadius shut himself up in his cell, on the doors of which were written the prophetical words: "Pitiable Greeks! why do you still err, and throwing away all hope in God, seek aid of the Franks? Why do you, with the whole of the town, which will soon fall, lose your Orthodoxy? Be merciful to me O God! I testify before Thee, that I am innocent of this crime. You see, miserable ones, what is doing around you, and at the time captivity is approaching you, - reject the faith of your fathers and receive unrighteousness! I shall never reject thee, beloved Orthodoxy; and will not conceal thee, Ο holy tradition, while my spirit dwells in this my body."
The inspired words of this monk roused the minds of the people. The clergy and laity cursed the union and all its present and future upholders. Everywhere cries resounded: "We want no aid from the Latins, we want no union, we will not receive the service of the azymites." The Orthodox Clergymen sentenced all who had communed with the Unionists to bear Church punishment. The great Church was quite empty, for the Orthodox would not visit it; Gennadius circulated pamphlets among the people full of enmity against the Latins, and exhortations to those of the union to cleanse their consciences from sin by strict penitence.
The mental disorder of the inhabitants conduced a good deal to the success of Mahomet's arms. The besieged inhabitants, instead of concentrating their remaining forces in the defense of the town, continued their religious animosity to each other. The Orthodox and Latins were constantly anathematizing each other. At last Constantinople was taken by Mahomet (May 29th, 1453).
The Sultan left the Greek Faith untouched, and appointed as head of the captive Christians the same Saint Gennadius, who had done so much for Orthodoxy even in the last disorderly times. He and his successors were good and strictly Orthodox Pastors of the overburdened, but as yet not fallen Greek Church. In the fallen Empire, the Church of the East presents to us a beautiful example of a nation steadfastly preserving the pure doctrine of its fathers, and of faith preserving the nation whole during the space of four heavy centuries. Like the Jews in the Babylonian captivity, the Greeks, on falling into the hands of the Turks, became still more strongly and firmly attached to their old faith; deprived of political liberty, and many worldly advantages inseparate from it, they found their sole consolation in their Orthodox Church. The Popes, by allowing the capital of Eastern Christianity to perish, only increased the animosity of the Greeks towards Romanism.
The Church of Russia showed herself a worthy daughter of the Orthodox Eastern Church, in her relations to the Florentine union.
With the title of Apostolic Legate to all northern countries, Isidore, at the close of the Council, returned from Italy to Russia, in hopes of alluring her to an union with the Church of Rome. From the capital of Hungary, he sent off circulars to the Dioceses of Lithuania, Russia, and Livonia, then under his jurisdiction; informing the Christians of the Latin and Greek Faith about the union that had taken place between the Western and Eastern Christians. Isidore wrote: "You good Christians of the Contantinopolitan Church, receive this union with spiritual joy and honour. I pray you not to dissent in anything from the Christians of Rome. And you Latin tribes, do not avoid the Greeks, avowed by Rome to be true Christians; pray in their churches, as they will also pray in yours. Confess your sins to Priests of both sides: from any one of them receive the Body of Christ alike holy in leavened or unleavened bread. So the Council, held in Florence, bids you do."
In the Russian territories, subjected to the influence of Latin heterodox power, Isidore could sooner meet with persons inclined to receive the union, than in autocratic Russia. But even in the former places his zeal met with an obstacle in the circumstance that Casimir, Grand Duke of Lithuania, had declared not for Pope Eugenius, but for the Council of Basle and Pope Felix elected by it. In Volhynia Isidore ordained Daniel as Bishop, who had agreed to the union, and then tried to defend the Latinizing Clergy from the hatred the Orthodox felt towards them, by means of his γάατα. In Kiev Duke Alexander gave a gramma to Isidore, as to "his father, the Metropolitan," over all his dukedom. The Kiev manuscripts affirm, nevertheless, that Isidore was expelled from Kiev.
In the spring of 1441, Isidore came to Moscow, bearing a very polite letter from the Pope to the Grand Duke. The clergy and laity impatiently awaited the Metropolitan in the Cathedral of the Assumption. Isidore came surrounded by a number of nobles, preceded by the Latin Cross. Relying on the simplicity and ignorance of his fold, he acted in a more decisive manner than his brethren in Constantinople. During the first Liturgy, the Pope's name was mentioned, and at the end of the service Isidore's Archdeacon read the Florentine decree from the ambo. All these news, as yet unheard of in the Russian Church, astonished both the clergy and laity very much. No one knew what to think of what was seen and heard. But the Grand Duke Basil Basilievitch, burning with zeal for the pure doctrine of the Church, solemnly, in the very Church, exposed the apostate Isidore, called him a false pastor, a corrupter of souls, a heretic, and at last ordered the unworthy Metropolitan to be led down from his throne; and, confining him in the Tchudoff Monastery, assembled a Council of Bishops and the higher grades of the Clergy to examine the decree of the Florentine Council. When it was found to be contrary to the ancient Orthodox doctrine, and when Arsenius, the companion of Isidore, had explained the way matters had been conducted in Florence, then the Grand Duke ordered efforts to be made to incline Isidore to repentance. But all was in vain. Remaining in confinement the whole of the summer, the pseudo-Metropolitan fled in the autumn from Moscow to Tver, very likely in hopes of receiving a better reception there, as the Duke of Tver had sent off one of his lawyers with him to the Council. But even in Tver he was received no better. The Grand Duke of Tver arrested him. Isidore managed however to escape, and fled to Novgorodok of Lithuania, and then to Rome, with the bad news of the frustration of the Papal plans. Thus, the Council of Florence, instead of reconciling the Church of Great Russia with Rome, or causing her to depart from Orthodoxy, only offered this Church an opportunity of showing her aversion from Romanism.
(this came in without attribution; I'll make enquiries)