I was bulimic as a teen and into my 20s. My thoughts are with you and your DD as you go through this as a family.
No pedometer, no 'extra' swimming, nothing out of the ordinary to help her 'work off the food'. Normal living is not like that. Helping her to make good food choices is what she needs.
Two or three visits to the counselor may not be enough to get a plan set for DDs eating. I would suggest that you keep a diary of what DD eats so you can share it with the therapist when you return. It will be helpful to know.
Help DD make healthy food choices and eat appropriately within all the food groups. Small meals are optimal (for all of us, really) but if that is not how your family normally eats then don't change it up -- consistency is what is needed.
Do not put any unusual focus on DD at meal time -- no one should 'praise' her for doing so well. She's not a baby being fed table food for the first time. If you are on the
DDP don't feel like you have to have her order everything that comes with the plan. She won't eat it any way so why put it in front of her and make her feel bad for not eating. If you are not on DDP and are paying out of pocket the allow her to order a small salad and have a bit of protein from your plate. Either way, do not put a HUGE plate of food in front of her, it's too daunting.
DO NOT, and I'm sorry for the caps but I want you to know I'm serious, let her get hungry. Really, make sure she has plenty to drink. Most likely she'll only drink water and that's fine. But there are plenty of places to get fruit or other healthy snacks. Watch to make sure she is eating from all the food groups. Cravings start when one of the groups is avoided and the brain wants it. Dairy and meat are big ones -- both are seen as high calorie and thus are often avoided. Serving sizes are not usually what is sold (sometimes they are 2 - 3 servings) so you may have to portion out the food. Small quantities are not as daunting.
And since she is 14, and likely still your little girl, you may feel that you should help her choose her food. Unless she is eating only 'junk', then allow her to make her food choices. If she is making poor choices then you should give her 2 or 3 things to choose from. If everyone else gets to choose, then she should be able to do so too. She doesn't want to feel like she is different or that the spotlight is on her.
Your daughter needs you to be her parent not her friend. At 14 I'm sure she wants to be independent but she may be overwhelmed by the freedom. Care for her like she's your little girl. It seems like everyone in your family is on board to help her -- just don't smother her will too much at once. WDW is not the place for her to have 100% independence. It is a family vacation and she is part of the family so she needs to participate just like everyone else. And just b/c other families allow their teens to roam alone doesn't mean you have to allow her to do the same. At the same time you don't want to make her feel imprisoned if she's had free reign in the past.
Just be supportive and encouraging. Make sure she, as well as you and your husband and other kids, are hydrated and nourished throughout the day with healthy snacks. Don't allow yourself or anyone in the family to become famished -- especially DD.
This might be what DD needs to get back in realignment that her family does love her and care about her. If you can do something alone with DD -- that does NOT involve food -- that might be helpful. Or if she has a great relationship with her dad maybe some one on one time so they can reconnect that relationship.
My heartfelt BEST WISHES!
to you. Bulimia is a horrible terrible thing to have to deal with. 
