My DD was doing this on a much smaller scale - calling us back in repeatedly for nothing. So, we would tell her that if we had to come back, I'd have to turn the light off, or her Dora doll/pillow couldn't stay in her crib, or whatever. We had to do it a couple of times. She hated it and cried to get the stuffy back or the light on, but we explained that we couldn't cuz we had to come back in. (I did make sure the door was open that it let in enough light so it wasn't a scared of the dark situation.) So what consequences can you assign to the behaviour - little things that she won't like but won't traumatize her? If it's not something in the moment, maybe it could be something at another time if you can explain that the bedtime behavior is the reason why she can't do something or have something. We have explained to DD that she can't have juice with snack (water was abundant if she was thirsty) because of some undesireable behavior in a store earlier that day.
