Wow. Their guardian angels were busy that day matching you up with them! This could easily have been one or more fatalities. How do you think his weight belt got so loose?
Likely the weight belt loosened up as depth increased and body compression occurred. The gas spaces in the gut compress, too. I'm a big guy and often find the need to adjust the cummerbund when I get to the bottom. Likely the weight belt wasn't particularly tight to begin with, too. Couple that with depth and off it comes.
Carl
---------- Post added June 2nd, 2014 at 07:14 PM ----------
You are probably already fully aware of the liability you assumed, unfortunately in our world today, many of our best deeds do not go unpunished. Obviously you did the right thing morally speaking, I just mention the liability because it seems like the right thing to do in a forum such as this. You did however, put your own life and livelihood in some amount of risk.
Unless he was a dive pro, he probably didn't incur as much liability. It could have been covered by Good Samaritan laws. Since any one can sue any one in the U.S. for any reason, it could still wind up in litigation until the judge dismisses the case based on the Good Samaritan laws.