What kind of trafficker is waved through then declares he has guns and asks where he can turn around? The CO should have acted on day one and waited to be ordered to lift the off limits order.
I don't mean to beat a dead horse here, because you and I are speculating, but if I were a trafficker that got caught that would be my story as well.
As it is, one has to wonder why anyone would inform the Mexican cops they were in possession. You and I would likely have kept our mouths shut, having knowledge of how easy it is for anyone appearing to be US military to get busted in Mexico at the whim of anyone wearing a badge.
On the other hand, I want to believe that this young Marine believed they would allow him to turn around.
The issue between you and me is whether the CO continues to fail to take effective action. Most likely the State Dept heard about it before the CO did and thus he may have been handcuffed from the beginning. Any unsanctioned action he takes at this point, given the international flavor, could have severe personal repercussions.