Though I appreciate the owning up, it's hard to believe someone would go out there without reading anything about the area. The first things I read about the trail when I googled it have to do with the monument and cairns.
"We saw several vehicles driving over the pile so I didn't think anyhing of it."
Unless his mindset changes, this guy will eventually get himself into a situation he can't get out of. I hope he is with other vehicles that can provide recovery and perhaps medical help when he does it.
I've followed him on Instagram for a while now because I like his rig, however, lately his posts (videos) are of wheeling off designated paths and blatant destruction of the area. For that, I have stopped following him. Its people like him and his buddies that get areas closed down permanently and make it increasing harder to do vehicle based adventure.
Signs don't stop some people unfortunately. Within the last few days there was a guy posting pics of his jeep in a creek witha sign saying stay out of the water in the forefront. I had to comment, nothing insulting but indicating what your doing is wrong.
As land and trails are being closed off, the realization that you can't just do what want needs to be achieved.
I respect that he apologized and owned up, but really man? A huge ass pile of rocks in the middle of a desert and you think it is just there to drive over? Seems like he would have had that thought running through his mind. Oh well.... life goes on. Hopefully no-one else does it. I do think there needs to be some sort of sign though, then the person would have no excuse other than stupidity or complete disrespect.