Change your flight from Qatar to Etihad, one of my relatives just went via Etihad and she had no problem at all. Layover in Abu Dhabi is only a couple of hours so there's no need to get to the hotel. Most of the workers at Doha Airport are Nepalese so she should be fine in either case.

Teach her small English phrases like 'Wheel Chair Please' 'Can I talk to Nepali' etc. That helps too.