150 seconds....24,000 ft+
As mentioned multiple times above the Captain returned to the flight deck 2 minutes and 46 seconds prior to contact with the ocean. So....giving roughly 16 seconds for him to immediately resume his seat. He would have been PF for roughly 2:30 and had 24,000 ft to work with.
He also wold have removed the most inexperienced pilot from the equation and given the senior pilot on the flight deck at the time of the incident enough time to make control inputs that very well might have shown the way out.
To me the the Captains failure to take what would appear to be the most prudent and responsible course of action speaks volumes about a poor criteria for selecting command pilots at AF. It still baffles me that the aircraft commander made no attempt to assume command of his plane.