I'm wide at the temples too, and the only helmet that worked for me was a Reebok one. I'd have him try on some different brand helmets and see if another one feels more comfortable. Because it would suck to play with that pain. Don't cut away the padding, just get a helmet that fits properly.
In seriousness now though look at the way the cage fits onc strapped on. Also maybe look into a different brand helmet too. Try some on. At 14 your kid could be going thru growth spurts I know when I was 14 going onto 15 I grew 8 inches in 1 summer! Hurt like a m**********r and my mom couldn't buy me new clothes/shoes quick enough. Look into it. Can't hurt!