There's no question that this would happen some day, but there is also no question that someone will get killed driving their car, etc.
The open question in my mind is was sufficient information provided (considering the possible language dificulties) to provide for reasonable informed consent? If so ... well, unfortunately bad things do happen to good people.
I've been on a JASA trip, to Tiger Beach, and I signed a stack of papers half of which strictly to make me aware of the danger of diving with ANY species of shark. I had signed and faxed all this before the trip, and they made me sign them all again! There was a shark briefing at the beginning of the trip, to explain about each potential species encounter and their potential dangers and behaviours and how to stay as safe as possible, there were also daily briefings repeating the safety measures, and when divers could not or would not follow those measures there was a repeat as well as removing unsafe divers from the water. I can not imagine how anyone on one of these shark trips could claim to be uninformed of the dangers.