In 2018, Trump gets 55 senators or more (likely) and Rs hold the House Rosenstein is likely gone in a year. I bet he doesn’t realize how tenuous is his position.
I suspect the 2018 mid terms are going to be a blood bath for the GOP, Senate turns blue and vast losses in the House...Then they will begin the process of Impeachment of Trump...and then the Impeachment of Pince..The GOP is very happy with that outcome..so they can rid themselves of both of them and to send a clear message to the voters “Do not ever do this again or expect the same will happen to them.”
Your math doesn’t work. You have to subtract the number of RINOs from the actual number of “Republican” senators then add that number to the total to determine if you actually have a majority number of votes.