Hello, I just got a heads up about your kitty with the ear problem and wanted to offer some encouragement.
I take care of a cat at my grandmother's that came up as a stray about 4-5 years ago. He lived outside but was very tame and was neutered and ear tipped when he arrived.
For the last several years, he pawed at his ear constantly and would periodically have the side of his face raw. We assumed he had ear mites even though we put Revolution on him when we could.
About a month ago, he looked bad, and was seeming to lose his balance sometimes. My grandmother was in the hospital and then rehab so my mother or I would feed him and another kitty outside twice a day. One night my mother went to feed them and he tried to get on the deck lost his balance and couldn't stand and was falling over and rolling on the ground. It was late at night and my mother didn't have a carrier, so she wrapped him in a towel and put him in a box on the porch and I went the next morning with a carrier to take him to the vet. When I got there he was gone and although I didn't know how he could have gotten out as bad as he was he had disappeared. We looked for him every day for a week and then a week and a day after we last saw him, he came back and was on the deck and very hungry. At this time he was unsteady with his head tilted to the side. I was able to get him inside for the night and next day took him to the vet.
Turns out he did not have ear mites, he had a tumor in the ear canal which was removed. The vet said these kind of tumors although considered malignant stay localized. That was about a week and a half ago. He did very well when he first came home, eating well, still had the head tilt, then he had a little setback and we started giving him ear and eye drops. On Friday, he was still eating but drinking little water, seems the head tilt has affected his ability to lap water. On Saturday, he seemed to feel bad so we took him back in and he stayed the weekend. He was dehydrated a little and got SQ fluids. He also received a steroid shot. The vet said it is possible that a small portion of the tumor was down deeper in the inner ear canal that she didn't get and though she can't operate there, a vet specialist at the vet school could. I live in a small town and this is a small vet practice. We picked him up Monday and right now he is much improved, walking much much straighter, able to jump up on things and very affectionate and comfortable. His eye is looking better from infection and he is eating real well, we are adding water to his food since he still is having some difficulty drinking enough water with the head tilt, but it also is getting better. Hes now living inside with my grandmother.
I just wanted to give you some hope, since it sounds like it could be the same thing with your Skye. Love Bug has had this problem for a long time and it sounds like Skye hasn't. If it is this type of tumor in the ear canal it is very operable especially if caught early and is not the type that spreads.
I hope you get some answers and wishing Skye the best.
If you have any questions you can PM me.