Too Many Straws
We all have heard of the straw the broke the camel's back. This appears to be another case of too many straws:
Rushed approach in IMC.
Turned onto final approach above glidepath, requiring throttle-off descent.
Radalt #1 locks onto false signal path and puts out -8 feet, valid.
GPWS sounds off with "Too Low, Gear", due to radalt #1.
Capt. EADI displays -8 feet, probably in a yellow meatball.
AT goes unnoticed into Retard mode, the throttles already pulled back in dispatched descent to catch the glidepath.
What we don't know yet is the "conversation" and other distractions being loaded onto the PF's brain as well, to the point he fails to react to decaying airspeed.
GB