With the number of different incendiary statements he made undermining the authority of his chain of command, he absolutely knew he was risking getting some charges on his way out. Under the UCMJ, anything your commander doesn't like can be treated as a crime and punished however he or she sees fit as long as they want to do all the paperwork.
Very rarely is an O-5 brought up on charges, but Scheller was begging them to do it. It's a brave act to lay down a marker that says he really stands by all of his rhetoric at the risk of losing so much, but he stated repeatedly that he wanted this fight.
Hopefully, he'll demand a jury trial and compel more Marine officers to come out of their hidey holes and either stand with him in allowing his open defiance to challenge the chain of command (which will for sure carry through and shorten their own career prospects) or show their slimy underbellies that they are fine with the terrible leadership.
To my knowledge, he never disobeyed an order while on active duty, or encouraged anyone else to do so. He expressed his views as an American citizen. Do members of the military forfeit their First Amendment rights while off-duty? If so, something is wrong.
Hopefully he’s got evidence triggered for automatic release in his absense.