OHH YEAH, HES AWOL (ABSENT WITHOUT LEAVE) AND ITS A JAIL ABLE OFFENSE. HE CANT GET ANY CREDIT CARDS, CARS OR HOUSES IN HIS NAME, HE ABANDONED HIS SERVICE... ITS ILLEGAL
If he didn't do his finally swear in at MEPS than it really doesn't matter.
It isn't illegal and after all this time and if he is your ex why do you care?
In his case yes, it's punishable, but if they find him, they will give a general discharge, so he can never come back and that's that. And if he's your ex then.....?