According to the series, several people (some accompanying her) were “commissioned” to assassinate Sophia if she ”failed” to “Romanize” the Rus church.
ST George was indeed Orthodox and Greek himself, same as Zoe Sophia Paleologina, and it was highly usual, as icons are still present in the monuments of "Byzantium" which is now in modern day Turkey and beyond this location, all the way in the east including Jerusalem and Palestine, evidence-based in churches built by St Helena herself also Greek and Orthodox. It still is very common to this very day! She, Zoe Sophia Paleologina, was Greek Orthodox, like St George, no matter what the Pope wanted her to be or St George to be and no matter where they, either of them, were geographically located, or their circumstances, THANK CHRIST. The models of Russian Orthodoxy were in the Eastern Roman Empire, as evidenced in the definitive pictures you use of St Peters Basilica in western Rome at the time, which are different, hence the word Basilica which defines that architecture meaning tiled two sided roof and not a dome shape. Although Basilica style churches are also found in Greece and /or the east. Although the word Tsar is derived from the word Ceasar being bit common in Western and Eastern Rome.