Questions sorry there's too much to read.
They say they let her in via the garage.
Does she have a car? If so was it parked there,?
My own feeling is this is a home invasion gone wrong, there was a person seen in neighbors back yard?. Person broke in and thought no one was home maybe gone away , especially if he saw the car.
Nancy comes home and he hides for a bit trying to get out, and goes to bed and he accidentally wakes her up, they fight dhd gets hurt, or killed and he now has to dispose of her body.
This is why cameras seem to dlbd disabled after Nancy got home not before and why he pacemaker stopped.
Now he has death of a famous person mum on his hands so to buy time makes up a kidnap ransom.
So did she have a car, where was if parked if so?
Was Nancy evening clothes she wore accounted for, if not did she actually go to bed,? How do they know she was in bed?
Is area remote, of so what tyres marks are there? How did the person get there?
Why did the camera doorbell not pick anything up, before it was disconnected, I'm.assumjng person broke in through the back...of maybe just to blow my theory out of the water, the had a leg yo the back door and was already waiting.