Warrior Final Attack after Big Bang

Final Attack only hits one monster unless you're using it with Slash Blast.

Does FA triggered by Slash Blast still use the following formula after BB? I am trying to see if the damage reduces for each mob in an attack like it currently does.

Slash Blast FA:
D = 2 * (1/3) ^ (OrderHit - 1)
Cumulative damage = 3 * (1 - (1/3) ^ NumHits)