Falkor

I found it. It was lower down like in the the pic you posted. Luckily I could get it unplugged without taking the bumper back off, but it was really tight. Just can't get the connections wrapped up, but it's in a pretty good protected area from water.

I got the best shots I could. I can try again if you can't tell what there is. But as you can see, there is no other plug behind the big grey one, and there is no other big grey plug under the headlight housing. I did have the bumper off last night to install Philips 12825WLEDX1 DRL's and saw the metal ribbed resistor, but I'm not finding any other plugs around the headlights.

I have a 2015 Legacy Premium 2.5i. I don't see the same thing that's in the pics. Would mine be different?