So sorry to hear Raindrop isn't improving as expected... I would strongly urge you at this point to take her to a Vet Neurologist, you may need to get a referral from your vet or the ER vet... here's a link to some in your area.... I would mention the possibility of her having GME or Chiari could they rule that out....
vet specialties neurology, FL 32233 - Google Search
Keeping you both in my prayers....