I'm looking at the kyphologic brace, but the only research I see is in 2009 and talks about in-brace correction only. Did you find something showing the final results? Or just that initial study. I agree that it would be good is there were something less obtrusive.
There's a group in Italy that I use as my go-to site for figuring out how people deal conservatively with different issues. Here's their article on exercise and bracing for Kyphosis - http://www.isico.it/isico/ricerca/pdf/ID00304.pdf
It's tough to have this happen to your kid. Don't beat yourself up about not noticing it - I think a lot of us have had the same experience. We're just not trained to spot this stuff. Hope you get lots of good info from your Shriner's visit.