The flightcrew didnt switch it back to AUTO for sure.Nor did they ever press horn cutout or operate the boom/mask switch or don masks.
What the FA who was also qualified as a pilot did with these switches 2 hours later is entirely a different matter.But the passengers were already dead by then werent they?
The engineer was not responsible I agree.
This was not a CRM accident.I dont agree the accident was the result of some company/culture malaise.It was a training/mindset issue and a wake up call to all aircrew of just how lethal and insidious hypoxia really is.Civilian aircrew dont even train it.If people are teaching it as a CRM crash,I disagree....both pilots were confused by the horn and suffered the same mindset.Crew coordination is immaterial to this one(except FA's-they saw the masks but couldnt or chose not to get into the cockpit??)