Listening to the last few minutes of cockpit conversation there is obviously a lot of professional work being carried out. But do we know who was talking and have we any indication that the captain was involved in this or was he the person mumbling "Oh God" in the background? - in which case he had lost authority.
Surely the main failure was the lack of fuel checks prior to departure. Calculate flight time plus additional times, check fuel uplifted, stick your nose (or something) in the fuel tank. I would hope that this procedure is mandatory before each flight.
Fuel is one of the few things that can cause an aircraft to stop in the air under normal circumstances, to not have enough at any time is unforgivable.