It seems to me the likeliest explanation is that the aircraft was still giving some powerful cues consistent with the erroneous interpretation. They must have been powerful cues because three men did not interpret a stall warning as meaning that the aircraft was about to enter a stall.
Agreed 100%.
I suspect the scenario will become clearer once we know what pitch information the pilots were seeing.
Also, note that the speed information displayed to RH pilot is not recorded. The PF was in the RHS. The PF may therefore have been reacting to speed information different to that recorded.