I think what we didn't see was when Skupin and Lisa were in the water and he basically said you and I are a team and let's consider all our options - could you ever consider switching? Looked like she was in agreement and they cut away . I would bet that she wanted to stay loyal so she voted the way she did but they agreed together that it would be okay for Skupin to help write the story for the good guys. Man I love Penner.
It fooled me - when Penner got that fourth vote I thought that meant Lisa and Skupin decided to stick with their original tribe. His heart must have been in his throat when Jeff read the last vote.