However, the cinematic left the question — what happened to the Archon? Was she dead? Was she just injured? Could the key be removed without killing her? Turns out, the cinematic did answer that question. In the BlizzConline WoW Q&A Narrative Designer Steve Danuser, confirmed that she survived. They wanted to confirm that, but were short on time. After Anduin takes the key, there is a quick shot where she moves her hand, and that was the evidence she was alive, just seriously injured. There will be more confirmation in the follow up quests as the story progresses when the patch launches.
I have to admit it wasn’t very clear from the viewer perspective. I thought she was dead too.