I've said several times now that her stacks weren't decreasing. I literally counted before and after on three different occasions. Each stack had an x turn single use note for duration and each turn until expiration and this was listed for all four buff types. So buster/quick/arts/crit would all say one hit each left for each turn duration remaining. So, after getting three arts hits in, all crits, it should display something like buster/arts/quick/crit up expiring in three different turns plus one round that only had something like buster/quick and either arts or crit and one that only had buster/quick. But that is not what was happening.
If the game was actually working the way the tooltips described I would have been able to get in a hit here or there, especially since the occasions when I was forced to use buster or quick would have at least cleared a stack of crit. But it did not work that way. Her buffs were not clearing. I had to restart and redo it with a different CE. Granted that the frequent stuns would also slow things done, progress still should have been possible.
Anyway past it now. Bugs aside, this fight seems like it was designed to be more frustrating than difficult as well as basically forcing the use of Castoria or NP drain strategies, which can be difficult to sustain.