EVENT

If there were any Experiment B participants that did not leave their rooms to help out (or just generally see what was going on) during the commotion in response to Nic and Dan's attack, something could have been seen on the cameras - if they looked at the ballroom.

The northern wall of the ballroom is floor-to-ceiling windows, as well as several patio doors leading out to a large patio. At the very edge of the windows, those with Ex B access only could have seen the little girl looking through and watching. No one in the room notices her. If someone from ExB ran downstairs to see her for herself, she would run away.