I think it might be closer to your #1 suggestion.
Yes, watch the video closely... The moment the "rings" come on in the back, you can see a reflection of the headlights in the bumper of the car in front:
I wonder how he knocked the headlights on briefly. Maybe one of those "pull back on the stalk" to "flash to pass" type momentary clicks. I think he was reaching around to roll down the windows at that moment.
( By the way, is that door closed all the way? The gap looks a little wide. )
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