Lurking newbie here.
I towed a 2000 Jetta, TDI back in 2000 so it’s the same beast as yours.
We had a class C 32ft Tioga MH, at the time and the company that made Blue Ox tow bars didn’t have the baseplate available for under the front fascia yet. So I participated in a company sponsored discount program. I hauled the car on a rented dolly out to Nebraska to the factory and left it for a week, while DW and I went to Yellow Stone. They fabricated and installed the tow bar baseplate and setup the lights while installing and working it out for that model of car. They did as described above and put another bulb in the rear lenses behind the bulb doors in each side in the trunk. They wired them separate from the car system to a 4 pin flat trailer plug in the front grill. Then when I hooked up the car I had a coiled cord that hookup to the MH and the flat cable in the grill. It all worked great and they never cut into my cars factory wiring.
I didn’t wind up towing the car more them a couple times. I will admit I didn’t do anything with respect to additional braking. I was on the fence at the time on if I should or not. The MH seemed to handle the additional weight just fine and I didn’t notice any additional stopping issues at all. But I was leery about what could happen in a panic stop situation and I intend on adding some type of additional braking before I towed it much more. Due to a job change and my time not being my own for a few years. We just sold the MH since we never had time to use it.
Retirement is coming soon and I want to do the Alaska things so and we are luring around here trying to decide what we should purchase. One days it’s a 5th wheel and the next it’s a DP, and then next a TT. So as DW says when you don’t know what you want, don’t do anything. Sorry for getting so far out into the weeds and off topic.