Yeah, I posted this before I beat the queen / got the true ending. I know what to do now. And for the pocket dimension in snowver, it's not ACTUALLY in snowver, it's right outside it. Once you exit snowver, you have to go to the next room, and you should find somewhere you can jump over with Rex. That's where it is. The walkthrough on here really helps, I recommend using it if you're having trouble with something.