You are only guessing about the language bit here. Just FYI, Loulan has yielded many copies of Vedic content but none related to Avesta. That should inform us directly that Sanskrit was known much better than Iranic dialects by Tarim Basin people
The Rāma Story and Sanskrit in Ancient Xinjiang – Subhash Kak – Medium
Even Sogdia had Hindu elements. Sogdian is an Iranian language though and so is Saka.
Here is a sample of Khotanese Saka.