It sounds like everyone tried to cut corners;
and now, you have, what you have.
It sounds like your Dad inherited the Mortgage; whatever it is; do you know?
I would think that he has to contact the Lender, provide the paperwork and see if they will deal with him.
She stopped paying the Insurance, and the Insurance companies won't insure anything if you aren't the owner.
Next, would be filing the Q. C. with the County Recorder; I would think.
Haven't done this, wouldn't try!