PoR - "Allow Mastering Spells" patch not working

[autofire372]

When editing Portrait of Ruin (USA), the armips patch to allow Charlotte to master her spells seems to apply, but no change in in-game behavior is observed; her spells still cannot be mastered.

I have verified that the dump I'm using as a base is a good dump, and the same patch works properly when the same rom is used with the randomizer (enabled via option).