The fainting story resonates with me. It's pretty simple when considering the other crazy stories going around.
Here is some reputable info on vasovagal syncope (Fainting):
www.mayoclinic.org
And I agree, "unconscious", whether 911-dispatcher-talk or not, does not make complete sense here in regard to horrifically murdered people and the scene(s) that go along with it.
If anything, the 911 caller(s) could rightfully be considered in shock and incoherent. If the callers said "unconscious" I bet it was in answer to a dispatcher's question trying to make sense of what was happening. Totally JMO.