Are you incompetent?
No, I am not clueless. Do you think there are athletes that are Adidas shoe sponsors and Nike clothing/gear sponsors? I have never seen an athlete be sponsored by Nike for clothing/gear, and Adidas for footwear in the sport of running/track and field. In case you forgot, our sport does not have much sponsorship opportunity anyway.
Nike and Adidas are giants in the shoe world and direct competitors. Champion is a clothing brand than most people don't even know makes shoes. Champion clothing sponsorship and Nike shoe contract is not the same as Nike shoe contract and Adidas gear contract.
If she had a Wal-mart contract do you think she would be expected to only wear shoes sold at Wal-Mart?