How old is the dog? I ask because I recently lost a small breed at the age of 16, for the last 2-3 years he was showing signs of dementia. He LOVED to eat, and I think he often forgot that he just had a meal. So, what worked to keep him comfortable was 3-4-5 small meals per day plus a bedtime snack.
I would consider consulting a specialist, a veterinary neurologist, maybe a little prescription medication would help? Maybe some more testing, after all, epilepsy is a neurological disorder.
I doubt changing foods would make much difference, although, I would avoid unnecessary additives, chemicals, supplements and such.
Maybe a grain free limited ingredient kibble as a base, you can presoak the kibble in water or plain chicken broth, it helps them consume enough water plus the kibble swells up and they think they are getting more đ
