It is not a good idea to not put her on the ressie and provide her a KTTW card. In August they are often checking cards at BWV pool I know for sure, and at BCV you will always have to provide your card to use the Stormalong Bay pool area.
Also, she will need it for the early morning park hours in order to be allowed entry. I would add her to the
DDP, make sure she knows she has to pay for this, and let her bring doggie bags to the meals.
And, I would also suggest to her parents that she get help for her eating disorder because that is obviously what is going on here.