The old guy is being selfish, imo. He knows they want him to retire, but he refuses and from the sounds of it
he's creating problems in the work place. At some point you need to call it quits and move on. He should be enjoying his grandkids, hobbies, spouse, etc. not working 8-10 hours a day.
If he needed the money that's a different story. There was a sad story of another older guy on here who was forced to work as an usher at the Jazz games just to pay his bills. I feel sorry for those types of oldoes, but not so much for the ones who are taking advantage of the system.