The wiring harness should be on the bottom of the bumper next to the receiver. If you have a receiver but no wiring harness (I believe this is how all the 1st Editions shipped), you can easily install this harness yourself. Takes a screwdriver and about 10 minutes, and you'll be ready to go. If you have a 4 pin trailer, you can connect /u/Nicht1menschlichFrau's adapter to this harness.
The socket they sell at the dealer is about $60, but you can buy the EXACT same one on amazon for under $15.
Pollak 11-893P RV 7-Way Socket (OEM) https://smile.amazon.com/dp/B000B6NQHW/ref=cm_sw_r_apa_i_88BR28NW57A0PFRG83G4_0
I've used it on my 2019 Atlas for the past 3 years. Plugs right into the harness under the screw plate you see there in the pic.
This is the OEM adapter that VW installs. I would just use any adapter for 4pin. You never know when you might need a 7 pin. I’ve only ever rented a few U-Haul so I’ve only used the 4 pin with an adapter. It’s honestly your easiest bet.
Here is a link for the 7 pin socket. The dealer will sell you the same thing for about $55, or you can order it here for about $15. https://www.amazon.com/gp/product/B000B6NQHW/ref=ppx_yo_dt_b_asin_image_o05_s00?ie=UTF8&th=1
Pollak 11-893P
The 7 way socket is $15 on amazon (https://www.amazon.com/dp/B000B6NQHW) and installation is a breeze. See this post vw id talk for instructions with pictures (https://www.vwidtalk.com/threads/trailer-light-parts.1664/post-21551).
I use a basic 7 to 4 adapter (Hopkins 47345) which sticks out a bit but not very much, and no issues connecting a 4pin trailer, ton of ground clearance. I just remove it and toss it in the trunk when I am not towing.
Yeah fuck that. US$13 on Amazon - Pollak 11-893P RV 7-Way Socket... https://www.amazon.com/dp/B000B6NQHW
My first reaction is not to trust this dealership. I have the AWD Pro S non-Gradient. I have had zero issues with the car since October.
I can confirm that the towing wiring harness is factory installed and your electrical installer is telling the truth. I ordered the Pollak 7-way socket (https://www.amazon.com/gp/product/B000B6NQHW/ref=ppx_od_dt_b_asin_title_s00?ie=UTF8&th=1) and installed it myself. I haven't tested it by hooking up trailer lights to it though.
As far as the FitCamX, I don't really buy that. There are multiple owners on vwidtalk that have installed that model dashcam and had no issues. I installed a BlackVue dashcam and wired it into the always-on overhead console power so it's active 24/7.
I'm at a loss for advice to give. I guess have them show you the "aftermarket module" before they take the bumper off and see if there is any truth to that claim.