And it's that quote that makes me believe that the girls were killed before they ever got a chance to go to sleep on August 12. He tells us his his normal routine of turning on the monitors, rain machines, etc. Looking back, it seems he was reflecting on how he felt in retrospect. Killing the girls on Sunday resulted in him not being able to turn on the monitors, the rain machines, or being able to kiss them in bed. Why would he have a reason to, if they were dead before bedtime?
Seeing BW sprawled out and blue on the monitor, IMO, was his way of adding a barrier to further detach himself from what he had done.
Based on that theory, I believe CW saw BW and CCW exactly as he mentioned, except I don't believe SW was anywhere in the picture, because I believe he did it himself. The monitor is just a story he told to distance himself from the grim reality of what he had done, IMO.
JMO.