Of course if the copilot were to "Incapacitate" the Captain could then decide his course of action based on what he feels most comfortable with. There is no requirement to land at nearest suitable and if the route to destination is programmed into the FMS and he does not want to divert or dump fuel he could continue to destination. A pan call is required.
I am aware of a USA to Europe flight that flew for over five hours and continued to destination after the FO incapacitated. The Captain said that to dump fuel and divert into a snowy Newfoundland at night would have scared the hell out of him but to continue to destination and his home base and land in daylight was very straightforward.
If the VS Captain had continued, unless it was the last flight to JFK, a crew could have been positioned out later that day to JFK to fly the aircraft back the following day. Passengers would not have known anything and the schedule would not have been disrupted. If the Captain in this case felt happier to return or was advised to then fair enough.