We might be talking at cross purposes - I am not disputing his actions prior to the flight, or his decision making leading up to his break.
As regards :
......the action / inaction of the Captain.
I meant that if Captains have never been given training how to recognise and fly out of a deep stall, then how was he expected to do it when he came back into the cockpit and undo the mess the other two had got into?