Okay, I'm sure I'm being incredibly dense here... nonetheless: Why was it immediately stated as cannon that Charlotte dies in that final scene with her and Daniel in This Place is Death? She appears dead, though not that much more dead than in her other unconscious episodes. Daniel never takes her pulse and doesn't check for breath sounds.
When I watched the episode for the first time, I thought the issue of her death was left ambiguous, rather than definitive. I think it's pretty likely that she is dead, I'm just not 100% convinced yet.