What do you do next?

The first thing you do is you OWN IT.... You F***ed up big time.....

I would move right imediately. Looks like bed surface there with no hangfire right below the rock. Also, probably no need to go back up but you could, looks like that hangfire ends right at the rock, so you could climb above it. Then what everyone else is saying, especially the part about the lottery ticket.

Getting off that pile of snow would be priority 1 for me. Sitting tight for a minute might let the snow he is sitting on bond back to the bed surface making it safer to get off his magic carpet there. If communication is possible no one should ski down in case they sent snow down which could start the thing moving again.

Looks like he flushed the little chute almost entirely; reclimbing it would be feasible. From the TR, looks like the bed surface skied ok, so it probably would've booted ok.

The hangfire to skier's right of the rib where he stopped would've given me pause, I think. Looking at the other photo of the skiers' right crown, it looks pretty tiny though. It all depends ...