Welfare Check
If I was a couple of hours from home and the police were at my door attempting to do a welfare check on my wife, there is only one thing I would say i.e. "break the f****** door down and get in there, NOW!".
The moment Chris didn't do this the police must have known it was him. There were of course so many red flags with this guy, but making the police wait till he arrived to gain entry when his wife could be dying somewhere inside (if he hadn't of course already murdered her), was one of the biggest.