@pyroholtz
I don't know if this helps or not, but if it is benign, there is a good chance for a full recovery.
My stepmother started showing similar symptoms about a year ago. Just as you mentioned, a scan showed a brain tumor. My father and stepmother live in Sarasota Florida, but my stepmother ended up in Tampa where there is better medical care. The tumor was benign, and surgery was able to excise it. My stepmother's mental abilities were back to normal about a week after the surgery. The surgeons were even able to do all the work above the hairline so that there is no visible evidence of the surgery.
I hope it is benign and that your mother can have a good recovery.