This is concern over several administrators in key positions who want to have the church celebrate homosexual relationships. They are treading carefully, because other Orthodox churches would not be happy about this, but it's clear that they believe that within Helsinki they will make this an acceptable lifestyle choice. One already sees troubling signs of this, like homosexual couples showing up at liturgy, hand-holding or hugging throughout the service, and then going up for Communion (any requirement of confession or even membership of the parish is rarely enforced for Communion here).
The greater Orthodox Church has always been able to deal with such infractions on established doctrine and practice. If the Finnish church went ahead and recognised, however loosely, homosexual relationships, much less solemnised them, the Church as a whole would regard the Church of Finland as no longer part of the Orthodox Church. Simple.