I guess if they prove him ineligible for office, he can be impeached or maybe there is an quicker remedy.
Well, no, actually, the rules for impeachment are well defined, and he would have to be convicted by the Senate and removes. Can you see that happening? At this point, if he’s found to be a poser, and ineligible for office, the remedy would involve removing every person who aided and abetted in this crime against the Constitution.