I've had insurance coverage through PASA/First Flight both as a recreational rider (before PASA discontinued it) and as an instructor. Luckily, I've never had to file a claim, so I don't have that first hand experience.
So becoming an instructor ; is the only current way to get liability insurance ; that
is what i may need to kite on Lake Mead
EDIT --- just read your post a bit More carefully ; they don't do liability any more .
And Thanks for the information : Bille