I have same issue with more challenges. All challenges ended on Sunday. I and other participant synchronized data but challenges are in "Gathering Results" state for several days.
Maybe problem is that other participant did not sychnorize data within 12 hours after challenges ended. He synchnonized later, but synchronized, so I think everything is prepared to complete challenges, but nothing is happening.
Today all challenges ended so maybe you need to wait few days. But I did not get badges for Challenge champion :-/
Are you referring to the weekly group challenges, or the custom ones you can create with your connection. It's my understanding that the Challenge Champ badge only works with the later.