Yeah, I had a LOT of fertility issues earlier this year. I realized my roo was not quite great at breeding yet, and all the fluff was in the way. I did AI. But I think if you trim them up right around their vent, it will work a lot better.
Actually, if you have the right bird, I think silkies might be the best bird you could use for showmanship!

We use a rooster, because you can position him well and he will stay in it, and he takes well to being moved and wings pulled on, etc. He works out better than most of our birds. At our last showmanship, my son used his favorite bird, which is a pullet and she did pretty good. She didn't want to stay in position when he moved her, but she wasn't bad. She takes handling VERY well. She just goes limp which is perfect for holding while you are pointing out all the parts. You probably need to use a different bird next time.
ETA-- oh and I am so sorry about your daughter's heart surgery. How scary!! I hope she is doing very well now.