Smiles4U, I think it is great that your daughter's great-great uncle wants to actually go out to eat. I think this would be great for him to actually go out and socialise. People who eat alone tend to not enjoy their food and especially seniors often get depressed and lose their appetite when their all by themselves. So going and eating in company is fantastic if he's fit enough to do it.
Maybe he could do a combination. Maybe get Meals On Wheels 4 days a week and go out 3 days a week?
By the way, the thing we suggested to DH's grandparents wasn't actually Meals on WHeels but some other company offering the same service. I can't remembre what they were called, though. Not sure if they're any better.
Saša