Here's what she had to say:
If she is 9 months post op, she should be able to eat salad, chicken, fruit etc.
My recommendation is to leave the park during meal periods and go to the Grand Californian and make reservations at the Storyteller's Café. Moderately priced and she'll probably be able to order off the menu (reservations at Disney-Dine). You can enter the Grand Californian either from California Adventure or from Downtown Disney (no need to go all the way around to the main entrance). If they are in
Disneyland, they can take the monorail to Downtown Disney and walk up a ways to the side entrance to the Grand Californian.
The Rainforest Café in downtown Disney has an extensive menu and I'm sure she can find something (reservations required, you need to call them directly). I've had great luck with waiters agreeing to modify anything for me. At the Rainforest during my last visit I had them change out beef on a salad and add shrimp. No problem.
In the park(s) I think she'll have more trouble. Most is fast food. The Blue Bayou is pretty limited (reservations required at Disney Dine), but she could probably just ask them for some roasted chicken and they'd bring it.
The only fast food place that might work is the one in Tomorrow Land (named something like Planet Grill). They do have a salad bar as well as Pizza for other folks.
Hopefully by now, she has found a protein bar that works for her. I'd bring a back-pack with protein bars, fruit and water and just walk walk walk and have a great time. PS they do sell water there, but it is Dansani, and I HATE Dansani. However if you are hot and thirsty, cold water no matter what brand hits the spot and keeps you hydrated!
Hope this helps.