Thanks @M.Seidam this was interesting one, and Watching it at 0.25 speed couple of times, my observations are :
1. The approach angle was not right according to me, he was hitting slip face, and that too in a kind of bowl what looks to me. I would either continue to ride the ridge and then steer right , straight down Or cross the crest straight up, straight down bcos from where he approached doesn't appears to be sharp crest.
2. When he arrived on other side, the minute he arrived, he was going down, but instead thought choose to counter steer and the sand wall started to build on his front right wheel, and he continued to counter steer, to correct his angle on a slip face absolutely not done. Looks to me, his front right wheel sand-wall caused this rollover. - There was NO way he was going to continue sideways (keeping in mind his angle of arrival on this side) - going down was only solution.