Any guesses on how far the light source is from my camera in that shot?
Appears to be a strong street light backlighting the vehicle and yard, and a weak fill light possibly below the camera (driveway light(s)?). Unknown angled surfaces make the location difficult, but at least one lamp is nearby. The fog is very light, near the level of a slight drizzle rather than fog. Removing the other house and lighting, the shot looks similar to my driveway lights on with the camera in IR-sensitive mode, with IR disabled. One light is 2 feet down, 1 foot over, and 1 foot back from the camera.
When we get fog, visibility is non-existent past a couple hundred feet. Bad fog provides no vision beyond 50-feet. The "IR" shot posted looks like what one would expect with IR when experiencing 200-ft visibility fog.
Infrared in general is poor for penetrating glass though. That's a different issue altogether and one would hope the vehicle's interior lights provide enough output to ID anyone inside. I know my dome lights are a nice 500 lumens of high CRI light in my vehicles, so output isn't a concern.