My cousin has celiacs disease, and I am pre celiacs (tested with high gluten antibodies, but no damage to the gut lining), so I try to avoid wheat and gluten in my diet. With celiacs disease the intolerance to gluten leads to damage in the gut lining of the intestines, which eventually can lead to malabsorption of nutrients, and ultimately death if a person who has the condition does not stop eating all gluten. Every time they have a reaction from eating gluten it contributes to the gut damage, some of which is repairable over time and avoidance and some of which isn't.
It's not just the common things labeled with wheat and gluten, gluten is in a lot of non baked goods and processed foods, so labels have to be read very carefully. Another thing that unfortunately affects people with the disease is cross contamination, if a food is made or processed where gluten/wheat products are produced it could cause a reaction.
It's too bad your friend won't consider raw, it might help to heal the gut, ear infections, and be easier on the digestive system. With the diet, she'll have to be careful that all the supplements, and foods used are gluten free, best to buy brands that actually state that on the package to avoid cross contamination with manufacturing processes. With the ear and skin problems, which may have came as a result of the gut being so off balance due to the celiacs, I would avoid any sugars/carbohydrates (grains, starchy vegetables, and fruits).
As far as home cooking recipes, with such specific health and diet needs, your friend may want to seek advice from an animal (canine) nutritionist.
I did find three home cooked recipes online that you could look into and see if they would be nutritionally sound to use. . .
You may want to check out Lew Olson's home cooked recipe, and substitute accordingly if need be, her recipes do recommend her vitamins that she sells.
Cooked Diet | B-Naturals.Com Newsletter
Monica Segal, a pet nutritionist, who has written a few books on dog nutrition/recipes also has a home cooked recipe you could look at and possibly make food substitutions if needed for the ear infections and celiacs. Monica I think also offers diet/nutrition consultations for owners with dogs with specific medical dietary needs.
monicasegal.com - Archive - Recipes For Dogs
Vet Dr. Greg Martinez has a crock pot recipe (I'm not sure how easily the bones cook down, and if you would have to add any more supplements that aren't listed, but it may be worth a quick read through.