What has Billy speechless? What question does the judge ask Billy?

Just as dawn is breaking, the dogs tree the coon in a tall sycamore. Billy manages to get it down and skin it; Grandpa kisses Little Ann. Now the judge wants to return to the old rail fence and investigate how the coon tricked the dogs. The judge figures it out and is astounded that Billy's dogs were able to finally find the coon. He assures Billy that he has a good chance of winning the cup.