Hmmm...regarding the third fog light.
When I first traveled to Europe in the early 1970s, these were required in Belgium and often seen in Benelux and Germany. Of course I'm not familiar with what were the rules and laws at that time, just anecdotal observation. They were always seemingly mounted under the rear bumper, left side. They had to be mounted low to be effective, as fog can and often does obscure tail lamps! That's why they created and in some cases, mandated these things in the first place. Just like separate fog lamps or integral fog lamps, they have to be mounted low to be effective. I cannot imagine how one mounted inside a tail lamp would have the same effectiveness, but hey--that's up to the EU to figure out.
Anyone who has traveled extensively in Germany when it is that season for fog, and encountered one of those horrific "Stau" where dozen upon dozens of cars crash in the fog knows how important these are. We tend to think of them here in the USA as cool options on an old car, but they were essential for safe driving.
My current daily driver is a 2019 Ford Edge, standard with integral fog lamps. They are the lowest lighting point on the front of the car. They only work on the low beam setting. I don't often encounter fog and thus have only used them a couple of times.
