Yeah, we've had trouble fetching the official/proper youtube songs when they're initially scrobbled through another platform. We do plan on allowing scrobblers to edit the links if they find it fetched the wrong one so it'll depend a lot on community input eventually and probably evolve into something wikipedia like where enough users need to vote in what they deem to be the correct one and it'll take the option of the majority.

Are you actually scrobbling the songs with the extension? That may be part of the issue but I'll look deeper into your reports here in a bit.