I was predicted 3 x A in 2004 before this A* nonsense, and I got rejected by 4 of my 6 choices. One of the places that gave me an offer was Exeter, where I went and had the time of my life alongside getting a good degree and doing extracurricular stuff that told me what I want to do in life, and lead to what I'm doing now. So don't worry, he'll be fine, get an excellent education and have a great time wherever he goes.