DW
No-one's saying the crew was "clueless", but let's be honest. If you're at full thrust, full back-stick and the aircraft is still falling - what else can it be other than stall?
.....a failure in the barostatic system causing not only erroneous speed indications, but also a downwinding altimeter at a never before seen rate (."...that canīt be.....") and a pegged VS?
Not saying that it was like that, just spinning your question a bit