The judge has to be involved in the decision to drop the case at this point. Pretty sure he can sentence based on the probation report and the defense arguments without further input from the government.
Flynn bears the burden on his motion to withdraw. So no need for the government to rebut that, either.
If the case were pretrial, Barr could dump it by just not putting on proof (although highly unlikely a judge would deny a motion to dismiss.)
Some judges will accept any agreed terms put before them. Others won’t. So small chance Barr orders it shut down and everybody from DOJ to the Judge goes along with it.
Smaller chance Flynn wins motion.
Best odds are still that Powell gins up so much indignation from the base that they beg Trump to pardon him after the motion is tossed and he is sentenced.
I will admit, the last two days had me slightly nervous. Feeling more confident today. (Somebody should add this to the record of **** to embarrass me with if I turn out to be wrong.)
JMO.