It seems most likely,finally, that the Pf was indeed the least experienced f/o ,in the rhs (frozen atpl) This leaves the other f/o as pnf in the lhs.acting as 'commander' in the absence of the captain.with all the responsibilities that involves.
no comment, but this sets up ...
it seems pretty clear that he had had no training whatsoever in sorting out problems of this magnitude,especially from the lhs.
I do not find your assertion valid, as I don't know what you base your "all or nothing" reasoning on.
Training and qualification are not a step function, they are part of a continuum.
I suggest that you go back and look up the experience base of the two FOs again.
probably never ever had to recover from a fully developed stall at high level in the sim.
Well, who has?
If you head over to the Tech Log threads on this mishap, and a thread on airliner stalls, you will find some people who understand simulation, its uses, and simulator programming issues.
Therein lies your answer: at this point, the fully developed stall, in the sim, isn't necessarily a valid training scenario.
Should it be? An open and much discussed question.