First, thank you for wanting to help this squirrel.
I agree this is a complex neuro condition involved that requires intervention by a rehabber. For the same reason of this case's complexity, I defer to those with repeated experience with neurological issues for meds.
My thoughts:
With such cases things can change and become destablized.
Since seisures were prior, not sure if this could be from roundworm or not, yet for now it isn't counted out.
https://www.thestar.com/news/insight..._backyard.html
This recipe you have posted has a fair to good ratio of calcium and magnesum of 3:1; yet the if stretched past 2 weeks the level of each would be too low. If MBD is involved, then it already is too low, and treatment would be needful. In this case I would include with the calcium protoco,l Magnesium glycinate powder from Swanson. This is a very absorbable amino chelate form of magnesium, so that its absorption won't compete with that of calcium, as it would with magnesium oxide.
Seizures lower magnesium when they occur, and bloodsugar. Hydrating, and increasing both calcium and magnesium is advisable.
During a seisure if you can and right after if you can't, put just a drop of organic maple syrup or dark molasses on the gums.
Even so this may be needful during or right after a seisure to help prevent another, do not add high processed sugar sources to the diet like corn syrup and cane sugar, or artificial sources either. Instead feed baked organic squash, and include organic yogurt with natural and low sugar content from Green Valley, or their Kefir lactose free. Redwood Hills Farms goat whole Kefir is a good source of protein and fats, that are easier to digest. If you use a feeding syringe, you can it with purified water, just be sure it is luke warm when you feed it by syringe.