Lastly the thing that doesn't feel right is the fact that salt water and electronics don't play well.
Sure the footage from the card would be recoverable to a degree, but still that would have gotten a hell of a beating if it was true, and surely more than a little damage to the card. Unless it was safely in a waterproof case, such as one of these...
You must have missed the recent post about the Canon Rebel lost underwater for over a year (http://www.canonrumors.com/2011/11/canon-rebel-1000d-lost-at-sea/). I'd be surprised if the card wasn't fine, especially if he got to it quickly.