Trump knows everything. At his Alabama rally last week, he said that people who got paid with things "other than campaign contributions" that Sessions is going to take them all down. It also makes sense why he never considered Trey Gowdy for AG, he needs him as an attack dog in Congress to keep everyone focused and in line.

He's getting fed real intel from people within the FBI and other agencies who are sick of the system of corruption and horrible crimes against humanity and want it to stop. There's a reason he has Flynn sit on his daily "real" intel briefings, it's to help him differentiate between what is the truth and what is bullshit on what they are telling him.