Allan,

Go ahead and put your hitch on and start towing, there is no problem.
I drove the exact combination in Germany a few years ago after the
worlds in Bayreuth. My cousin leant me his VW Golf Combi TDI which is
essentially the same model as your Jetta. I was so impressed when I
returned to Toronto I was determined to buy one. As it turned out I
was a few years too early the Jetta station wagon TDI in North America
was still a thing of the future. In Germany I carried 5 passengers
towing a glider trailer and was only slowed down on the steepest
hills, even then it just kept pulling, just a little slower. Best part
of the story is that this was a driving school car complete with dual
controls and 280,000 km on the odometer.

Go for it!