So it’s supposed to end on a cliffhanger like that, but just framing things out: Cheng Xiaoshi got out of the photo at the time the attacker went to check on the noise, thus we don’t know what happened after CXS exited the photo. There’s still room for deliberation for the reason why she’s not dead at time of the incident, maybe prolonged death (since presently, the result is that she’s still dead either way). So it might be a surveillance or photo of her moments before she died. This is all just purely my analysis of the ending without spoilers (I did watch the entire seasons) but I hope this eased your confusion why Emma is still alive in that scene. :))))
