In this scenario, how would you explain that radio was not used for MAYDAY
Human nature is at play here also. Whether it be as CC said, crew working too hard to make a call, or mind closing down by the reality of imminent death, I don't know, but aircraft have crashed with what seemed like ample time for the crew to holler something on the radio, but they did not. There's been grunts and groans on CVRs, but not much on the radio.