If you do not find anyone, I suggest put in request for wheelchair. She does not have to be disabled, she can just use it. I did this for my parents, and had mom use the wheelchair.
Boarding is a breeze from JFK if you do so. Just hand the guy rolling the wheelchair $5-$10 and your mom will board the plane with ease. Just have her wait in the flight in Abu Dhabi and someone will be there to pick her up and take her to her next connecting flight. Mom said no-one showed up in Nepal with a wheelchair (on either legs of flight). Its sad, but I wasn't surprised.
Use wheelchair, even if you find a companion. My mom is 60 but was tired/exhausted/overwhelmed by the flight. You will also make the companion's flight boarding easy by doing so. Good Luck!!
