If I had to guess and its only a guess,I would say he was a good swimmer and knew the paddle board well. The fact that he was seen by an eye witness to have fallen off the board,losing his balance suggests that he well might have had head trauma and it was effecting him.
I’m no doctor but from what I hear head trauma can be delayed. This sounds like that. But, who really knows. And with zeros guy doing the autopsy we probably know why that is happening. No telling what is being covered up but you can bet a lot of evidence is now gone.
It was the vax.