First, I've been so haunted by this event, and this board has helped in knowing so many fellow divers are so equally disturbed, thanks. Thoughts and prayers to the families and all that are close to the operation.
I'm resolved to the idea that the fire started in the bunk room, and everyone succumbed to smoke inhalation in their sleep, as they say is the case in home fires without a working smoke alarm. I hope they come to this conclusion, and quickly for the alternatives are truly nightmarish.
I've read a lot of this thread, but admittedly jumped to the end at about page 50 as there was much repetition and speculation based on early and inaccurate reports. My thoughts and observations:
The captain of the boat that pulled the Conception to deeper water so the fireboats could reach indicated the first four recovered floated to the surface at the time of the sinking and he helped recover them.
There was a statement that all the bodies would need DNA identification due to extreme thermal damage, indication no one made it out and into the water.
Based on my stay on the Vision four years ago, there was a 120V outlet between the topmost single bunks that could very likely have been used for recharging batteries at night (the charging station in the rear of the salon was always at capacity). There was nothing said about not using these outlets for this purpose, but then this was before the infamous Samsung phone combustion issue and recall.
As was mentioned, the electric generator and air circulation system made for a lot of white noise. Also with so many people a strange noise at 3AM wouldn't likely be cause to investigate, and by this time and two days of diving everyone would be sleeping hard. My single bunk had a ventilation outlet that with my privacy curtain closed created positive pressure of clean air that isolated the bunk from smells (and therefore smoke). I don't know if all bunks had this ventilation, it was nice and would make sense from a comfort standpoint.
The forward 1/3 of the boat was the most consumed by the early fire, idication it did not start at the stern and probably not at the charging station at the rear of the salon. Also note the apparent early hull burn-through at the waterline; possible indication it started low, like in the bunk compartment. The fire would egress up the staircase, i.e the forward section of the boat.
After writing this I found this article with the same theory by the boat's designer:
Theory on Conception dive boat fire points to phone-charging station
