Appears to be caused by the fix for this:
http://forum.caravelgames.com/viewtopic.php?TopicID=39947
tl;dr - Body-killing friendly monsters no longer breaks stealth. This room involves killing NPCs, which are always friendly. Since the custom role is based on Wraithwing, which has stealth by default, the room now works differently.
The hold author will need to supply an updated version to the HAs to fix this room. The easiest fix is to have an NPC in the room waiting for a monster to die, which then disables the player stealth.
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