I don’t think you’re correct. They may not have extradition treaties, but they also don’t want to negatively affect relations with the successor for nothing in return. They aren’t going to defend Putin, because most of the world, and especially the Russian successor, would be after him. There’s just no benefit. They may not extradite, but they won’t host him either (outside of a prison). He’d likely either be held in captivity or executed, if he isn’t extradited, or let The Hague take care of him.