Thank you for the update! It's very promising that Gracie is showing signs of controlled movement! Good you are pursuing her ongoing care with your vet - it sounds like the transition from her original specialist to whoever is covering hasn't gone smoothly!
I wonder if Gracie is anxious in part because she's not used to being in a separate room from her people, even though she can see all of you? Would it work to set up an x-pen in the family room, so she's a bit closer? Is she able to be with you without a gate during periods when Travis is napping or at a playdate?
It also sounds like as a family, you could use a bit of a break. Are there other greyhound people in your area that could maybe babysit Gracie now and then for a couple of hours so you all can go on an outing, or so you can get some rest?
You've probably thought through all these options - they were just the things that I could think of. Wish I was closer and could help more practically that just wishing and praying for things to go better for you, but for what it's worth, there are a lot of people here beaming you support and healing thoughts for Gracie.