We Yanks love a good mystery.
That explains a lot!
and I've got news, rarely will a body sink for at least an hour or two! The human body is lighter than water. Until the water saturates the tissue, it remains lighter than water. However, if ya drill enough holes in it with an AK, you can speed the process! I don't think this is the case in this situation.
Even then, within 24 hours, the decomp supplies enough gas to lift it to the surface! In salt water, they don't sink at all, without help from the local sharks or the asshole that ties an anchor to their ass, that is!
Just how many "bodies" have you seen in water? Oh I get it, you're relyin' on what you read on the internet. Must be true, right?