Kennel cough diet

Our daughter p/u a female black lab @ the local dog pound. Took her to the vet for a check up. She has a bad case of kennel cough and the vet gave us a list of food items to mix w/ canned dog food to feed her for the next 2 weeks. INSTANT oatmeal and rice were among them. Is the instant real important? I have only reg oatmeal and reg brown rice so cooked up a batch of (3 cups)regular oatmeal and with some grated steamed carrots, scrambled eggs mixed this w/ a large can of ALPO. She is on 2 RX's as well and in isolation from other dogs. Oh, and ice not water. Even beef broth ice or gatorade ice but no water while she is being treated.