On the CVR transcript, HOT-2 appears to mention the EFI source source select switch as though he has selected alternate. I believe he now is looking at output from the center symbol generator. A minute and a half later he's speaking as though he no longer has airspeed, perhaps there is no drawn airspeed.
Shouldn't the source inputs for the center symbol generator be the same source inputs for the center autopilot? The autopilot that appears to have been engaged throughout the entire flight?