You know, I'm trying to think of other things these three people had in common. I feel certain Charlie was never involved with Widmore in any way; it seems we know a lot about him. But we know a lot less about Boone and very little about Libby; except for the weird fact that she was in the Santa Rosa Mental Hospital. I guess what I'm getting at is this: could Penny have revealed something to the Oceanic 6 while they were on her boat? It's only after spending time with her that they've come up with this story. Maybe she new something about Boone and Libby not yet revealed to us.