Perhaps another anti seizure drug could be tried. My dog was on valium for years, and this seemed to lessen the frequency of the seizures. He ended up having only 1 or 2 a year. Ask your vet if this is a possibility. Perhaps you need a second opinion from another vet. Then there's always the vet schools, which are expensive but worth the try because they usually have the latest treatments and drugs. Sending prayers and hugs, and don't give up! We're all pulling for Bud and you!
Rita
Buttons the new princess
Andy and Champ, at the bridge
Nicky, the Tennessee Walker