I'm probably the only idiot in America who has had this experience, but...
I've been on the AK Safari ride a least a dozen times and the last time I rode it the ride was extremely jarring. I remember actually thinking, "Gosh, this seems a lot more jarring than I remember." about one minute before our vehicle lurched hard and I jammed my finger against the seat back ahead of us. Ouchie-wah-wah!

I've never had a finger get popped out of joint before and it was sure painful until it went back where it belonged. Sorry to be graphic. Just wanted to throw out there that some rides you might not think about being rough actually can be.
BTW, sorry this happened to DS just before vacation. My DS is also 14 and I know having to skip his favorite rides would really bum him out.