I think trump doesn't even have to be in Congress. They can elect anyone speaker. The only way it would work though is for Joe to be 25th'd, and Kamala sworn in, but not confirm a VP. Then they have to have some incredibly bad dirt on Kamala, like the most blatant illegal thing you could imagine that would force her to resign.

I think it would have to be done like that because I just can't imagine a scenario where they'd impeach them both.