I don't think it is, but congres was trying to remove president multiple times. In the end it is more about legitimacy than law itself. Congress and vice president seized power without proving democratic mandate (doesn't mean that they don't actually have it).

If we use USA as example, congress can legally ignore results of presidential election and choose president themselves. It would be legal but not legitimate.

Again I don't think that is the case, but I'm not in any way certain that this isn't a case.