No, I wasn't with Robert from 3 Vallées.
My brief misgivings about flying had passed by Sunday lunchtime. I'm looking forward to flying again this weekend!
It seems that the accident was probably caused by a problem with the right ski on the aircraft. We took a lot of photos of the damage, and think that the right ski rotated relative to the undercarriage on touchdown, causing it to dig into the snow and flip the plane onto its back.
The skis were fairly lightweight electrically retractable ones. I've decided to stick to heavyweight hydraulic ones from now on!
I could be wrong about the cause..... but it seems by far the most plausible explanation.
Thanks to all for the supportive comments.