This Judge looks like he is willing to play hero. If Flynn tells the truth about Mueller's threats, the judge will throw the case out. The Judge also has the power to go after the Prosecution. They can't bother Flynn anymore if the Judge calls them out for misconduct
If Flynn's associates go through to trial then most of DC will have to be charged. What a pickle! Flynn can't be sentenced until a bogus case is complete. The bogus case is going to go away one day without prosecution.