I ended up selling on stub hub. I think if you were to white out the under 18 and then making copies you would be fine as they are identical to regular tickets otherwise
My guess is that since they will be one of those print at home stub hub tickets is they either won't look any different than the regular tickets or it will have youth written somewhere on it. With thousands of people going through the line I doubt a ticket reader will look carefully enough...
So on Stub Hub today i accidentally bought 4 youth tickets for the Wyoming game instead of adult. I'm wondering if my group of 4 adults will be able to get in. They are instant download and I'm wondering if youth tickets look any different than the regular from stub hub. Maybe I can fold it...