First that would have triggered impeachment the next day. That would chew up the House and Senate for months when we need other things done.
Second, there's a persistent myth that someone else besides Sessions would have stopped the coup. That's ridiculous, no such person exists. The coup will simply have to run out of gas, sputter and die politically. That's been baked into the cake from day one: political with no criminal action to justify it. So it will have to die from lack of political support (other than the minority of Trump haters who will always support any fantasy).
It isn't going to run out of gas. Without supervision and with unlimited funds from the deep state, Mueller can go on as long as the President is in office. Mueller can spend as much as necessary to harass and ruin everyone around Trump. He has made it clear that the price of being a prominent Trump appointee will be having your life and the lives of your family turned upside down. Congress will not cut off the money. Many of them are avid supporters of the soft coup. So unless Trump fires as many as necessary, they will slowly bleed the Administration to death and stop Trump's agenda. If Trump fires the coup plotters, he might be impeached, but Muller will not stop, otherwise. There will be more high profile indictments and plea bargains. The next one is likely General Flynn who will have been coerced to give damaging statements in exchange for a shorter prison term.