I kind of like the second, or some combination of both. Here's an idea:

Since he can't be out of the camp alone, Crow will be with Hazel (she would want to keep talking to him about his illness to see if she can come up with a better way to approach it). I was thinking Penelope could find him while they're out and he would send Hazel back to the camp to warn the others about the knights. That's the only way I can think of that he would end up alone with Penelope. After that, we could go either direction with them escaping together or Penelope doubling back to divert the knights away from him. I'm good with whatever feels more natural in the story ^^