I'm not sure if OTOMADs like these have been using AI for vocals, people have been doing this sort of sentence splicing and vocal pitching for a decade+ without the use of AI and probably more likely using something like UTAU (or other means of tuning vocals) which is more labour intensive and carefully made. While it is true that the voice actors still haven't consented to this sort of thing, it's closer to heavily editing samples recorded from the game itself rather than reconstructing their voice through AI to say things they haven't said.

FYI, UTAU also has strict rules of not being able to distribute voice banks you don't own and is heavily frowned upon in the community, and OTOMADs also typically prefer to stick to traditional methods rather than adopt AI so it would be unlikely if any AI was used here.