Device stuck while reading the control units at 16/22

This is OK.

What this is saying is that your MK6 Golf car "could" have a possible 22 modules associated with that chassis (no car has all 22 modules.
The SCAN (autoscan in VCDS terms) is stuck on the 16th possible module for that chassis, but it isn't saying that it is stuck on Module #16 or address #16.

You can easily go around this by NOT doing a SCAN, and just going to each module directly to get your desired results (the icon with the 3 horizontal lines in the Blue circle). You will see the problematic module when it shows that it is enabled, but doesn't respond when you tap on it to get more information. In my experience, this is usually incorrect coding in Gateway #19. I've seen this happen all the time for MK5 Golf vehicles that have either the Generation2 or Generation3 steering rack incorrectly coded for the steering angle sensor (module#4). In this case, Right-Hand Drive MK5 Golf with the Generation 3 steering rack do not have a separate steering angle sensor in the steering column, but one built into the steering rack itself. In this case, the Steering angle sensor is logically installed, but not actually addressable by OBDeleven or VCDS (but the gateway still needs to "know" that it is there).

The point I'm making is that what is happening to you is not abnormal for some car configurations. You just have to manually identify the problematic module first before you can see how it connects to the gateway #19 and the other devices. The MK6 Golf is just a restyled MK5 with a better engine, so the electrical components are the same (but higher revision numbers).