According to the contracts Mr. Trump with The Apprentice, he is not allowed to use the term, fired, you’re fired, or “don’t let the door hit you where the good Lord split you,” unless he does it during a regularly episode of his hugely popular show.
This is apparently why he has been unable to fire Attorney General Jeff Sessions. According to White House sources, there is a chance he will get AG sessions to participate in a survivors series next year and then he will be able to vote him off the island.