I placed a copy of your post on our Parkinson's forum also -
Atypical Parksinsons/General Encephalopathy

Are you able to get access to more medical details - past testing & results reports, drs notes on symptoms & diagnosis?
She may need to give written permission or medical power of atty so Drs can talk to you.
Did she gradually lose abilities over the year? or was it a dramatic acute change?
How long ago did she start Carb/lev? before the loss of function?

Any second or third opinions?
alternative/naturopath/ acupuncture? Just mentioning alternative options.
It seems like she lost function quite quickly, I would want to know why & how if it was my loved one. I'm guessing they ruled out stroke.