Just a comment: we have a lady from Jerusalem in our church who sings in Arabic at every Divine Liturgy.Beautiful, absolutely beautiful.
I'm wagering you already know of the Melkite Sr. Marie Keyrouz. She's proficient in many Rites.
I once purchased Marcel Peres' Chants de L'Eglise Milanaise
, different from other Ambrosian chants in that it is performed as the director thinks it sounded like in the first millenium. Ergo, an Eastern influence is observed, and to my surprise and delight, by voice recognition, I found out that amongst the members of Ensemble Organum was Sr. Marie Keyrouz. And I must say I was stunned by her good pronunciation of Latin (which is why I had some doubts it was her). Arabs are not known for proficiency in their phonetic grasp of that language (French on the other, is another matter; they tend to be excellent in that area).
Her performance, needless to say, was beautiful. She added a strong Antiochian element to the chant.
In IC XC