In real world anything could happen in times when you thing everything is perfect. Accidents happens. These times are hard for tour operators and people even more.
Incidents against Tour Companies can be difficult, even if, on the surface, they seem straightforward, and appear to be caused by negligence on the part of the tourist. T
Zanzibar local experience do not hold Public Liability Insurance, if something happens whilst you are on holiday in Tanzania it is your own travel insurance that will cover any costs involved. Please make sure you have sufficient insurance cover before travelling to Tanzania or Africa.