That is too broad, there are things such as the 'but for' test, which attempts to find as well as limit liability simultaneously.
ie: but for the cruise being held, would the incident have occurred? or is it but for the actions of the party at fault in an accident, would the harm have been caused? it would be the latter, duty of care revolves around whether the person organising the cruise was put in a position where there was a special relationship with the person suffered harm, quite arguble as in 'how was this duty different from other road incidents under the same circumstances, albeit organised?' was the actions of the tortfeasor (person at fault) were such where the harm suffered to the plaintiff was that reasonbly expected?
the only way this would come to be fully understood would be in each individual writ/civil case. disclaimers do not waive complete liability especially where there is negligence or other fault elements in failing to provide an adequate duty of care.
there is never an true and clear cut answer.