The Citadel Dungeon is the one at the base of the tower, near the Lake Shrine. You need to go into the top room (with the Skeleton) and get the Scrying Stone, then use it from your inventory. This will give you the chance to get the Toshan mindread.
Giving the stone to Romon without using it yourself will make Toshan's mindread unobtainable.
Good to know. Maybe someone should edit the first post with that, cuz you can use this stone only in this room and not everybody use it.
