When Russia wanted some kind of encryption keys he could not hand over because they dont exist, Telegram was banned in Russia but people found ways to use it anyway. So I dont think Russia has anything to "force" Durov other than via Apple/Google. He doesn't live there or owns anything there and according to past posts of him and there are no Telegram servers there either. + The proxy stuff to circumvent Russia's ban is already implemented if they would block the IPs again.

It seems very likely that Apple/Google is actually the problem here. I encourage everyone to download the app from the website or F-Droid not form Google.