Heroes vs villains bug - players choose the same hero

While playing heroes vs villains on Endor, all but one player on the opposing team chose Leia Organa. The other player chose Yoda. The opposing team camped and set up 3 shields while Yoda buffed them up. They obviously won the match, but this isn't supposed to happen. You're not supposed to be able to choose the same hero. You would have multiple Darth Vaders, Bosks, Lukes and in this case Leia.