I have circled the area the vent would be - nothing but metal behind it.
To the left? Fuse box, thick bundle of wiring and battery.
IMHO, I don't see how this vent is going to do much good other than collect dirt and dust into your engine bay - there would be minimal to no gain from having a vent in the headlight.
Also, adding the vent only complicates the design (turn signal relocation and wiring) and drives up the price.
