It doesnot matter whether the person speaks English or not. I will give one idea but it sounds funny. Think abt it
You can take any route
Print a paper with the following information
1. Name of the person travelling.
2. Transist point with all the details of flight.
3. Also write that the person can only speak Nepali and can understand some hindi ( i guess).
4. Say the person to wear that paper all the time so anyone inside the airport can assist the person to the flight.
5. At the point of final destination, you will be there to assist the person.
NOTE: Dont forget to write your contact nummber and the contact no. of Nepal.
Definetly, the person will reach the destination withour any hassel.
any more information... Post it here... I will help u