He was denied the ability to travel (US revoked passport) while making a connection in Moscow. The US's actions trapped him there -- it was not his destination. Do you believe he had any reasonable choice at that point but to accept the asylum subsequently offered?
There is a thin line between bold statements that lack nuance, and plain lies.
Order of events are relevant. It is important to know how he ended up in Russia in the first place, long before this asylum. And was declining the asylum really an option?
The US government canceled his passport at some point between him being in Hong Kong and the Moscow airport. So the claim he "fled to Russia" is a lie. He was exiled to Russia by the US officials who actively removed his ability to leave the Russian airport.