No FBI employee has the right to work whenever or wherever he/she wants to work. He/she accepts the assignment given to him/her or he/she should be fired or quit. And certainly the President nor the FBI director nor the A.G. or anybody else should be required to keep anybody in a position in which he/she committed malfeasance.Civil servants have protections against political retribution.
That’s how the government should work unless you’re corrupt.