Thanks for the thoughts. I would not completely dismiss that her floor licking could be partly a stress behavior, but we are a fairly calm household (I know that what I consider calm may not be calm for a certain dog). And I will certainly keep the idea of an Adaptil collar in the back of my mind.
Right now, we are working with the theory that the licking may be a sign of an 'imbalance' in her system, and that this 'imbalance' could lead to seizures. Her nervous system may be acutely sensitive to diet (see below). The TCVM vet suggested feeding her meat broth (not bone broth) for a couple of days to see if her floor licking behavior changed. And it did! The floor licking dramatically decreased by at least 75-90%. But obviously, she can not live on meat broth so she went back to the raw diet with additions and changes to the Chinese herbs prescribed based on this new information.
Unfortunately, she has had one (or two) more cluster seizure episodes. And they are dramatic - with 10-14 seizures within a 24 hour period. I feel so bad for her, but on the other hand, currently the episodes are spaced about 3-4 weeks apart, and the remainder of the time, she is a happy, normal dog.
The TCVM vet has admitted that she has never had a dog NOT respond to a raw diet combined with Chinese herbs. (And my dog is also on Keppra and Zonisamide prescribed by a traditional Western vet. Both vets are aware of the 2-pronged approach, and are fine with it.)
The latest approach is a GARD diet. The belief is that her system is so sensitive to glutamate and aspartate (neurostimulating amino acids) that they have to be severely restricted in her diet. I certainly hope it works for her. She has now been on the GARD diet for about 9 days, and the floor licking has decreased significantly, but is still happening at a lower level.
If the GARD diet doesn't work, I have one last resort - to get an MRI to rule out (or in) a brain tumor or brain cyst - both of which are low probability. Luckily, I have just heard of an equine facility about 90 minutes from me where I may be able to arrange an MRI for about 35-45% of the cost of an MRI at the vet teaching hospital. (I live about an hour away from the vet school at VA Tech.)
Such a learning experience. Darn these border collies that are pharmacoresistant to anti-seizure drugs.
With regard to contacting the breeder or sibling owners: I have not thought about pursuing that avenue, but the dog has sort of been passed on, and I am her 3rd home. I do know she has a couple of dogs in her pedigree that are a couple of generations away that did produce some epileptic pups.