Yeah I just tested it and hilariously, the "dead" person got up and ran out of the door!
My original plan was to have the player enter an empty place (in this situation a small Arachnos base) find the body, and even if they can't click on it, click on a nearby object which triggers an ambush of troops thinking the player is the killer. I can make that work, except for the empty map part. It looks like the MA won't let me set up the map with no "enemies" already in it.