@jcris, Sorry you're going thru this. I have a few questions.
1) Is Princess still showing extreme sensitivity in her face and bottom when touched as she did back in January or has this disappeared? And is Belle still showing signs of anxiety or dementia? Are they siblings?
2) If you pursued this, what are the brand names of the fish oil and CBD oils you use, and how much/often are they given this? On this I would want to rule out recalls for those products in case there have been bad reports. (This is a long shot, but some of these symptoms in both dogs remind me of lead poisoning.)
3) Is Princess's recent stumbling always in her
front two legs, or have you seen any tripping due to stumbling from her
rear two legs? Did your vet do "the knuckling test"?
If not, try this now. You fold your dog's foot under, like in this photo:
If your dog doesn't respond by putting it's paw back in place, it means the nerve signal from the foot is not making its way to the brain, and is indicative that something is going on neurologically. DM typically begins in the back legs, not the front. You can learn more about that from this vet in
this video.
You can also save money on at least one lab fee by first ruling out Degenerative Myelopathy (DM)
here for $58 if the vet charges more for this. It's a saliva swab test and you can take the results to a vet neurology specialist, but there are other types of tests (xray, MRI or blood work) to rule out other conditions including inflammation or infection, which you can learn about on
this other video.
I truly hope these suggestions help and that whatever is going on is reversible or can at least be slowed down.