You would be surprised he will heal quickly barring any complications from his previous rads. I had 30-40 percent of my tongue removed and was sitting on a beach in Mexico literally 17 days later. And enjoying the buffet. - I had 40 nodes removed from my neck as well. Muscles cut etc... Soooo I've been there. If he keeps up with his oral hygiene and starts therapy for his shoulder and neck and does his tongue exercises, you will be surprised how well he will do. Tell him to stick to soft but controllable foods - scrambled eggs, omelets, pancakes etc... For a while put the food in on his good side, in small amounts then swallow with water.