I'm so sorry that you are going through so much. Maybe the OS will accept your A1C where it is especially if it has been going down. Can your primary care doctor help out and talk to the OS?
You will make it through the revision and recovery ok. It's hard. I've been there. Mine was only 8 months after my TKR. I found it was easier to recover from my revision than the original TKR. The first few days were rough. I just made sure that I always took my pain meds around the clock and iced and elevated. I have three small dogs to take care of. I bought a 'water cooler' for them that holds about a gallon of water. I fill it up as much as I can so they don't run out. You can use a lead that is long enough to let your dog out. I had a 'cookie' for each one that they loved so they would always come right back. I also put wee wee pads in the family room just in case.
I put some frozen dinners, veggies that can be steamed in the bag in my freezer. I picked up fruit cups, cheeses sticks, crackers and pretzels. I picked up bottles of water and other small bottles of juice. Anything for just a quick snack.
I think your recovery will be better because this time you will get a knee that functions correctly.