Before you go in guns blazing, confirm some info. For 2015 the Q70L "performance wheel and tire package" was just the 20-inch split 5 spoke wheels, 245/40/20 tires... AND the Akebono sport brakes.(those are the big silver ones that say "Infiniti" on them)
They might have just copy-pasted the original specs of the car, which happens to humans. If you don't have the original window sticker, I'd do as Larz advised - spend around $10 for that Monroney label that will tell you exactly what your car (and VIN) came with for options.
However, zooming in at the imgur album you provided of your car,
https://m.imgur.com/a/1bFfzGv, I can see that you have the Akebono brakes. Your wheels are from a standard Q70L alright, but something must have been manipulated for you to receive it like that. The factory certainly did not typically provide those brakes with 18" wheels on the M/Q70.
So someone either installed the brakes or switched the wheels.
It's just a matter of finding out who did it - previous owner or dealership.
[Hmmm, I wonder if they used wheel spacers or if those 18s clear the brakes naturally.]