Here is what I believe is a first hand account: http://www.scubaboard.com/forums/4852846-post11.html
From what I got from other posts/boards it was a RB diver who was at technical depths, and he was brought to the surface by buddies. I have no further information as to how many hours he had on the unit, his experience, or whether anyone has figured out any possible cause.
It’s been a rough week for RB divers as there was another RB death on the Vandenberg the day before (11-13). http://seaduction.com/scuba-diving/vandenberg-death-rebreather/