In some countries carrying pax under IFR or at night in SE aircraft is prohibited (don't know about Kenya). He was probably a low time CPL as this sort of flying is an entry level job, along with scenic flights, instructing and right seat on turbo props.
Going out to a safari camp there probably wouldn't have been any approach aids or radar control and the aircraft GPS would be VFR only. Had he descended in cloud to the lowest safe and not been visual he would have had to divert. Stay VFR and find a hole is the best decision in a lot of cases.
