I don't own that trailer, but, I need to caution you on "balancing" your rig. Travel Trailers (TT) are designed to be safe with a tongue weight of between 12 and 15% of the trailer's gross weight. Below 12% and your odds of the "tail wagging the dog" increase exponentially and leave you with a very unstable and unsafe towing rig.
Your trailer is going to be over your hitch weight, even with the minimum 12%. The gross weight of the 189FDS is 6025 lbs and that would equal a tongue weight of ~724 lbs. Storage space on virtually all trailers is found in front of the axles to make sure that the tongue stays heavy enough to be safe and that is the biggest problem with toy haulers; very hard to make them tow-stable when you load the toy area with heavy toys.
My recommendation would be to get a Sherline Scale
and load your trailer up with what you would expect to be taking. Keep the heaviest stuff closest to, but, on the forward side of the axles. That keeps the tongue weight, but, transfers the least amount to the tongue. Once you are loaded, take your weight measurement with the Sherline scale. You may find you are over loaded on the tongue weight as allowed by your Toureg. At that point, you need to decide what you want to leave at home. You don't want to start moving stuff to the back. You aren't going to lighten the overall weight of your trailer by doing so, but, unloading the tongue at that point will be lowering the percentage of tongue weight which leads to dangerous handling / safety issues. That's why trailers designed to carry really heavy loads always have their rear axles at the back and not towards the middle; it forces the tow load to be placed on the tongue.