They have not failed, The Evacuation is a DEMONSTRATION, it is not a pass fail, when you Demonstrate the partial evac you have two attempt, if the first one does not meet the requirements you have a 2nd chance, if that does not work you have to reschedule and do it again until you pass.
BLTA passed the evac demonstration, however it was a mechanical discrepancy that made FAA ask for a redo. Since they succeeded time and performance wise BLTA were allowed to move forward with the table tops.
Once the Mechanical issue is resolved there will be a redo of the Evac. This time it is more looking at the mechanical issue with the slides.
