CG report indicates that a commercial passenger vessel crashed into a kayak ejecting the two occupants of the latter.  The male occupant suffered serious injuries (reports of skull fracture, water intake, pneumonia) because he was trapped under the hull of the commercial ship for 2-5 minutes after the event.  The commercial operator was at fault for not havinga  proper lookout and being distracted by personal electronics (text messages, streaming content).  THe recreational operator was also at fault for inexperience.  The rental agency did not provide a briefing on the craft and the operator didn't have experience with kayaks.