Have you read "The Plot Against the President" by Lee Smith? If Horowitz has followed the same leads as exposed in that book, or at least checked into its description of what happened, a bunch of FBI/DOJ folks should fry. Comey, McCabe, Strzok, Yates as a bare minimum.
I'm reading The Plot now. Came upon the following today (pg 165).
"Because Nunes had uncovered the [anti-Trump] operation, he had to be crushed. 'Finding the unmasking was really deadly to them' he says. 'And it should be, and they should all be investigated, and people should be thrown in jail for it. People should be in jail for a long time for what they did to Flynn and others.'"
This is Nunes speaking after his role was largely over and the IG and Barr/Durham teams had taken up their work. The investigations of the plotters is well under way and people will go to jail. I am confident of it. I would add Brennan to your "minimum" list