After reading your original post again, I just have to wonder, who was more disappointed, you, or the kids?
If you do not mind me asking, how many other Gelbvieh cattle were there to show against? Do you have pictures?
Even if a judge knows your breed, some times they will lean toward cattle that type more like the breed they are familiar with or raise. Your calves may be top end Gelbvieh but if the other calves had traits he liked more, you will slip down in the class.
If their not deep ribbed, big hipped, clean necked, with some thickness it will be hard to compete, I don't care what breed you bring. As Knabe stated keep working on improving your herd and have fun (it is supposed to be fun).
We towed calves around for 8 years, won our class several times, had a few calves in the drive for their division with one reserve, but more often than not they set in the upper end of the class but did not win. These calves were purchased for our county fair, and we had a couple champions and reserves over the years.
What we did do is make allot of friends, spent quality time together as a family, and the boys learned about work and reward, the harder they worked the better they did. We would do it over again the same way.
After reading your original post again, I just have to wonder, who was more disappointed, you, or the kids?