I'm with Cym: if I had been asked for more info, I'd have submitted video. I think you know a DYS kid when you see one a lot of the time, and video gets around the handwriting problem that's so common and the "Is this good enough material" issue. If it's the kid in action, the kid you see every day doing whatever it is that makes you think s/he's HG+, then it's good enough. Video of a child thinking through math problems is a lot more persausive than just a piece of paper with problems on it, you know?
Plus it would be a lot harder to fake video than a piece of paper, so I think they'll be more likely to accept video. (Just my opinion, with no basis in actual knowledge.)
And I'll add my standard note that for DYS purposes you want to distinguish between material that shows your child to be "merely" GT and that which shows him/her to be HG+. (I put "merely" in quotes because, of course, it's such a ridiculous statement!) For DYS, performance should be 3+ years above age level, so it might pay to familiarize yourself a bit with what is being taught in school to kids 3 or 4 or 5 years older than your child. If your child is doing that and then some, then illustrate that as best you can.
