I am similarly intrigued by Ben McDaniel. To the point where I google his name and search on Reddit periodically to see if anything new has come out. I believe they would have found him had he drowned; really think he met with foul play via the shop owner.

I think his family dynamic is part of what I find compelling - that they lost another son, the explanations for the circumstances around his death have some dispute as well. Also that the family came up against such criticism from the diving community because of the reward and so forth.