He is desperate because the end is near for him. Even this will not save him. He has a date with the military tribunal and hangman looming over him.
I don’t think I’m aware of the situation you address there, but it doesn’t surprise me that he might be up on charges soon. That group of folks who were best chums at the FBI need to be prosecuted.
There are clear conflicting interests which should have prevented Mueller from every being appointed.
It’s like he was appointed to make sure none of his chums became targets, pure and simple.