My "proof": the strong resemblance with the iconostas screens in the following three old Byzantine churches in Greece:

* Oratory of Santa Maria in Vale in Cividale del Friuli;
photo Luigi Zilli, Officine Fotografiche Friulane

* The St. Nikolas Orphanos church (XIVth c.) in Thessaloniki;
photo Lykides, Thessaloniki
This beautiful, small church has been used for expositions the last few years; this is the reason why the essential elements of the iconostas screen have been removed, just leaving the columns and the architrave, just as in Cividale.

* The Hosios Loukas church (XIth c.) in the monastry of the same name near Delphi;
photo Editions "Hannibal", Athens
By the way, the two icons by Damaskinos have been stolen in 1980.

* The Protaton church (Xth c.) in Karies, Mount Athos
photo Lykides, Thessaloniki