Is buying the food that he likes off of the internet cost prohibitive? We received a pretty old guy last April.... We played the food shuffle for about 3 months until we found what he really likes. Our case.. Nutro, Natural Choice, Senior, Toy Breed, chicken, rice, oatmeal. After finding it, the store quit carrying it, food shuffle again until we found another source for what he liked.
The funny thing with ours, he didn't consistently like ANY wet or moist food, no matter how expensive. Mamma tried dozens. LOL Of course he loves nearly anything off of our plates to supplement his dry food.