I have a related question: How about a character finding out that they are already dead and then seeing their own death in flashback (a la The Sixth Sense)?
If the character continues to exist in the same form as they have throughout the story, then maybe the MCD tag isn't needed, because that character isn't "lost" to the reader. On the other hand, if "seeing" the character die is the important thing, then the tag ought to be used.