I'm a scientist, not a pilot.
It seems that the biggest source of uncertainty is what did the pilots know and what was their assessment of the situation.
There seems to be a lot of debate as to whether they were aware of or had reliable data about speed, pitch, aoa, etc. But, we know that they were aware of their altitude and rate of descent as they passed through 10,000 ft. Even so, they continued to pull back on the stick. Is it possible that they believed they were in a steep dive rather than a stall?
Is it possible to get a stall warning when pulling out of a dive?
Isn't a dive is more recoverable than a stall? With "no other indications" is it not possible to fool oneself into believing the more hopeful scenario?