Russia was one of his last choices as a refuge; they were just one of the only countries to accept him.

I doubt he's fond of Russia, either, and he's made some passive-aggressive jabs at them on his Twitter.

That said, it can't be ruled out that he divulged even more secret information to Russia's intelligence services as a condition for asylum, but I don't think there's any evidence it was one of his motives when leaking.