So sorry for your loss, Barry, and for the man's family and other friends. That's tragic. Be assured of my prayers.
Were they able to say what happened? Was it a heart attack? Do you suspect the episode actually started in the boat, which is why he tripped and went overboard in the first place? Or was it all the effort/excitement in the moments that followed trying to get him to shore that it went from bad to worse?
Prayers up.