You can cause someone enough inconvenience without diverting. Get him on the black list and offloaded by police on arrival. Two or three of those will be enough of a deterrent to everyone else who decides that COVID doesn't apply to them. The regulators need to wake up and actually make their "recommendations" enforceable until such time that concerns of mass contagion are no longer a thing. The one and only way to actually reinstate some confidence in people that safety measures are not just a salesman's chatter to lure them into booking.