i think its a fairly safe fold . i think i would have lead out with a bet with my open ended straight draw on the turn. that way when he bets into me with his possible flush on the river it probably wont be an all in. and i can call his smaller bluff/bet.

if he's a good player he shouldnt be on tilt from losing one buyin. but calling an all in with a flush draw is by far one of the dumbest moves i've seen.