I am happy to hear about the dental..that is terrific news!
As for hypoallergenic food, ask him about some RX foods...I have used Royal Canin Hypoallergenic foods...you need a prescription for it.
As for home cooking...I would not do that without a recipe from a vet nutritionist. I use one here in Houston but there are some websites where you can get information...you MUST have supplements ... it is not as simple as just cooking foods that you think are ok. You can use these two sites for information:
Welcome to Pet Diets www.balanceit.com
Also, if you are interested in a consult with a vet nutritionist, you can find one at:
acvn.com Your vet could call one for suggestions and you probably would not have to pay...unless you went with home cooking.
Keep in mind that usually allergies are not related to food. My experience has been more environmental.
As for adenomas...I have left some, but it depends on where they are and if they are bothering the pup...then I have them removed. You might ask them to consider removing some during her dental.