Sadly, this man made poor choices that were way outside the scope of safe diving.
If he was an instructor, this will be the most important lesson that his diving students ever recieve.
There is really no place for diving like this. If a dive site has a deep bottom and you plan on going there, a single Al80 just isn't going to cut it.
One of my dive buddies lost an instructor for very similar reasons, in a cave environment.
Heres one for a try, train for the environment you wish to dive in and then follow that training.
This diver was not fit for this dive environment, and could not save his own life much less handle a camera at the same time. Underwater video and photography are very interesting and fun to do, but one must be able to handle the dive before adding cameras and toys.