If anyone else is struggling with this bug, it's been fixed! All you have to do is start the client in windowed mode by pressing Alt+Enter. If you login, the pokemon should no longer be locked. After that, just logout and login again and the fix should persist. GLHF!
I know this might be impolite to ask, but can I get some compensation for my account being unplayable? I'm pretty poor in game so a few mil would be nice