She knew there was nothing else to do because the villains would never turn on Russell or Parvati.Candice would not switch back to the Heroes because Russell had an idol and Sandra didn't switch because Candice told on her for almost switching. She could of kept the idol clue, but she was too nice. Living up to her true hero. She could of maybe said "Ruppert is a clear, more threat", but she didn't. She did want to go out as a villain.