I have never been to the sale but this is what is listed on their website:
Please note: Buyers must register for the Outlet Sale. One registration per individual. Name on ID will be checked against your registration confirmation. Vera Bradley reserves the right to void any duplicate registrations. USPS will be on site throughout the sale for customers to ship purchases home.
This would lead me to believe that everyone that enters must be registered, therefore your daughters would need to register too. I think this would be how they control the number of people that can enter. You may want to call them to get a definite answer, Vera Bradley Customer Service:
(888) 855-8372 .