I can't help you except to say that perhaps you should consider finding a
better vet.  If you have an urgent care vet facility in your area, they
often have a very high caliber of emergency and specialty vets.

I wish you luck getting to the bottom of this.  I hope Peach will be okay.

if your vet can't figure it out  new vet on specializing in epilepsy  my
rumble is epileptic  his blood work was normal  than he became diabetic.

If he has another seizure you need to pay very close attention here to these
8 rules. This is from personal experience

1 don't panic   most seizures last on 30 seconds even thought it seems like
forever
2  DON'T PICK UP THE FURBALL unless he or she is in danger of striking a
object or falling off an object.   They can
    inverntely hurt you and themselves
3  observe how the body is reacting such as back legs constricting  a
strange twitch.  Observe how they react afterwards
4   talk soothingly to them you can stroke them it helps them come out of it
quicker.
5   REMEMBER DON'T PANIC.
6   write everything done this is an emotional time and you will forget
things
7  search your home to make sure the furball did not get in any chemicals or
household plants.
8   take a deep breath again and clam down  some cats have a seizure and
never have a seizure again in their life.  It is not             the end of
the world even though it seems like it to us.

Trust me I went thru what you are feeling right now.  Helpless ness the
feeling of like you were rode hard put up wet and than b@tch slapped.
    Long story made short.  I snatched up Rumble and made it to the vets
office which is 20 minutes away in less than 5 minutes with two police
officers hot on my tail. In tears the whole time  thinking I was going to
lose this furball.  The vet asked me all the above question which I could
not answer  luckily the officers where animal  lovers and saw Rumble have
another seizure right in front of the vet who was able to diagnose what type
of seizures they were. To this date 5 years later  cause unknown went to all
the specialist spent almost $10,000 ( no joke) to find out why.   Luckily it
has been a year since he get off the medication and no seizures. YEAH HAPPY
DANCE