The importance of AoA probes... and FAC's.
The FAC computes a/c gross weight, and displays limit speeds on the PFD - below 14,500 ft. the FAC uses AoA information as opposed to a "memorized" value of GW. Hence the need to do this test at FL 140 max - for up-to-date values of Vls etc. - to FL 100 as a minimum safe altitude for the test.
In Normal Law the FAC displays Vls, α prot, α max on the PFD speed scale. In the case of this a/c with erroneous fixed AoA values who knows what value of gross weight the FAC's computed? The fact that the crew slowed down to less than 107 kt (the calculated Vmin elsewhere in the report) indicates to me that perhaps the computed minimum speeds were less than the true values - but I don't know for sure. Another clue is the fact that the A/THR mode never went to αFloor.
If true, a further complication would be that Autotrim did not stop as the speed reduced through the true Vls.
Once in Direct Law with TOGA thrust, THS further nose-up than normal, lots of trim wheel movement would be necessary to gain a decent amount of nose-down elevator authority.