My question: What does Flynn know that has the FBI et al. so worried that they wanted him out of his position as National Security Advisor?
He would have rooted out all the participants of the coup attempt.
His original crime was against the chosen one’s effort to try and wipe fedgov systems of anything that stated muslim=bad. Obama wouldn’t want to offend the brotherhood after all. Flynn knew that would hamper intelligence efforts so he tried to sound the alarm. The fact that Trump picked him must have pissed them off.