It's simple. If they raise their head, Fox News knocks it off. The GOP primary voters get 90% of their news from fox, so those guys are scared shitless. If they say anything they will get primaried, if they don't they will get some of the blame for the smoking pit that will be left of government when 45 leaves office. But that is down the road, and those guys being human, are going to put that off as long as possible.
45 is trying to bait the Dems into impeachment. He's at home in the courts. {4K and change of cases he's involved in on either side} He knows the senate will not vote him out, so he playing with house money. He figures, just like with Clinton, his numbers will go up with impeachment. It may be just what he needs to win re-election.
Please don't fling me in that briar patch.