I've traced it down a bit more loading quite a few old saves. It appears it may not be tied to just the tiefling party. When I load my game from the goblin camp before finishing the quest lines there I can sleep and end my day. From my save in the defiled temple where i entered from the goblin camp after the puzzle i do not have the ability to sleep/end my day anymore. No amount of waypoint jumping or hopping into the tiefling celebration seems to work.
