Have her checked for amelanotic melanoma. It's a very aggressive form of skin cancer that often gets misdiagnosed and the prognosis is poor once it is discovered. We lost our dog Rhubarb to it, and it had actually formed on the back of her tongue. She went through the same thing with the seizures and incontinence. By the time it got properly diagnosed, it had metastasized and the seizures were due to the cancer spreading to her brain. It's a horrible thing. I give annually to the Canine Cancer Society now.
i was thinking the same thing, get her checked for cancer. get a blood cbc and serum panel done, so they can look at her blood as well as various enzyme levels, do it all in one blood draw. getting both done will ive them a lot better picture what’s going on. with her being diabetic it’s better to get it all looked at now. might be good to get a chest xray and abdominal xray too to see anything unusual right away, that would confirm the bloodwork results.