if u were hit on flash crash and your stop loss wasnt hit, and u end up with owing them 20% of your capital?
No reason to let BFX know who you are, and if they did you didn't sign anything, at least not related to the account you margin trade on.
BFX is a little weird when it comes to flash crashage, they're crazy conservative on leverage yet stop cascades easily bring stuff to zero. Compare with the BitMEX swap, even with half the degens at 100x it doesn't zap you like that.