I've been running ghetto for a few months now and been very pleased with the results. 20" Schwalbe BMX tube, Mavic 519 rims and Panaracer Fire XC Pro 2.1's.
Last night on a ride, I went over a little jump and ended up a couple of feet in the air, got a bit of a tweak on the launch and landed slightly rear wheel first, at a bit of an angle. Rear tyre burped out a load of it's air and sealant but stayed on the rim and sealed itself up perfectly. A few strokes of the minipump and it was back up to pressure (about 35-40psi) and held up for the rest of the ride and is still up this morning, so it appears no lasting damage I'll just top up the sealant today.
So, in summary:
Ghetto setup at <35psi + 100kg guy + 2ft squiffy landing = about the limit in my opinion.
Panaracer Fire XC Pro 2.1's.
That's your problem, not anything else.
Panaracer are notoriously poor at sealing in tubeless setups, the fact you got them to seal at all in the first place is quite impressive. Change to some other tyres (Maxxis, Bontrager, Kenda to name but 3) with more reliable beads, and then give it a whirl again.
I've done the same to my "2bliss" Captain on a Crossland wheel, basically a pukka UST setup, no more resistant to squiffy landings than Ghetto IMO...