Alzheimers and Frontotemporal dementia misdiagnosis?

I was notified today that my mom (59) was diagnosed with: “Major Neurocognitive Disorder due to Alzheimer's disease. Frontotemporal Dementia”

5’6 and I don’t know her weight

I am wondering if those can be wrong, and if she actually has Wernicke-Korsakoff syndrome. Context below:

I don’t have a lot of first hand information on diagnostics that have been run because I was low-no contact with her and her husband before things got as bad as they are now. Getting info from aunt and uncle who the husband talks to sometimes.

She has been an alcoholic for a long time. Every time I took her to detox, and that was a lot of times, she would be treated for severe B1 deficiency. When she was drinking, she would have terrible speech and memory issues, but when she got sober (and probably some b1) it would get better. Every time she relapsed the symptoms took longer to go away…. until one time they just didn’t go away. I always suspected she had Wernicke-Korsakoff because it really seemed like she was developing dementia that got worse every time she drank.

I couldn’t get her to go to the doctor and the hospital didn’t run extensive tests on her any of the times she was there. I dont know how long (if at all) she has been sober now because her husband had no interest in helping her stay sober (would buy her alcohol).

Either way, he is an addict himself that has always been paranoid and strange when in active addiction. I know he had been for at least the past few years although I am not sure about the last few months. If he is in active addiction, I could see him lying about, or not disclosing, how severe her alcoholism was/is.

I don’t know how any of these things are diagnosed, so I guess my questions are:

-With the tests run, is it even feasible that she was misdiagnosed with Alzheimers and frontotemporal dementia?
-Would it change any outcomes?

Thank you for any insight. If you need more info let me know.