The "treason" question was (to me) an un-asked for gift. Because I don't think the Judge is in on it, I could be wrong, but I think the Judge was angry and confused that Flynn was surrendering without cause to a corrupt charge from a corrupt investigation. For him to bring up the word "treason" as bait for the Media, would have to mean that he was involved in a "conspiracy" and I don't think that is a chance they would take.