Hello. Not sure if the correct procedure is to reply here, or start a new thread, but ...
I managed to knock all of Auntie Ethel's masked thralls unconscious after entering the area behind the fireplace (before the showdown with Auntie Ethel).
It seems to work fine, but as soon as you removed the mask from the final person (I checked twice, it doesn't matter who, just the last one of the bunch), they all die. Like D-E-D.
Is this intended? I am very disappointed, sigh, spent such a long time trying to figure out a peaceful solution to this.
Yes, this is intended. The lore reason is that "their mind collapses", or perhaps it's a failsafe in whatever deal they made with Ethel. Normally though, you remove a mask, that person dies on the spot. Only one of the 4 can be saved, and it requires passing up on a major reward. However, once they're knocked out, they're dead to the game regardless (since they were red type and not yellow type enemies). You already were far past the point of being able to save them.