Unfortunately I can't hit any of them with my bow or with any offensive spells. They're all on the other side of the wall, so even though I can sometimes see them I can't fire anything through it. And many times I can't see the monsters at all, I can only see their red dots on my minimap. When I leave the room and Mardaneus kills everything, I can walk around and find their bones.
It's a pity, but I have to wonder if the FAQ is even correct. Has anyone here ever gotten that bonus? I wonder if the guy was mistaken.