There's no "shut lid", simply a bunch of unknowns at this point and a bunch of stunned and shocked friends that are trying to make sense of it all. What we know is that for whatever reason, our friend lost consciousness on the descent at a depth of approximately 180' and the people he was diving with made a valiant effort to get him to the surface and save his life.
Was the root cause hyperoxia, hypoxia, or a medical event? We do not know at this point.
I've known Joe for almost 30 years, we talked at least once a week on the phone about everything from jokes to cave diving to deep reef/wreck diving to just family stuff. I am confident that Joe would have wanted any information out there that would lead to an improvement in diver safety, that will be honored.