All you have to do is look at the video of him trying to swim laps in the pool to see that he was at best a marginal swimmer - even in a pool, and wearing flippers. Also appears to be a "natural sinker" - which is consistent with his body type.
Put a very poor swimmer, with negative buoyancy, in open water, at night, without a PFD. If he tips off a paddleboard unexpectedly, chances are good he panics and drowns.
I am an excellent swimmer, but I would NEVER go on any kind of watercraft without a PFD.
With all that said, I think there is a coverup in progress, but it has less to do with the victim than who was present, who made the call, etc. And the reflexive response of the Obamas to everything is coverup.
He is back stroking in the video. And someone is timing his laps. .....
. Regarding the pond, he should have been able to swim enough to go maybe 20 to 30 feet til his feet hit land.
Hell He could bounce up , grab air, get his bearing. And maybe 5 to 7 strokes away was shallow enuf for him to stand. The whole thing. STINKS.