Intuitively, I'd have thought that a ditching in that area is due to a propulsive failure or more immediate in-flight emergency that made staying airborne an even worse option. Also even a single survivor indicates strongly that the ditching was controlled.
A pilot of that age almost certainly has competent map and compass skills, and any pilot of any age nowadays will have a handheld GPS on board on a long trip. Those, in the conditions described, make navigating a serviceable aeroplane to a runway and landing it pretty straightforward.
I'm not a betting man, but if I were, I'd put my money on a problem on the aeroplane and a controlled ditching.
What does not seem at-all unlikely however is that whilst the pilot may have had a good idea what the problem was, his priority was not to getting that information accurately to his wife or anybody else. His priority surely was a safe ditching and saving first his wife's life and then his own. By and large he seems to have succeeded.
G