VW's info is confusing. I would ignore it. The same thing comes up if I input "2016 DSG", and I know I don't have a "torque splitter". The only thing I have is a rear "center" Haldex, and you change it every three years/30K miles.
Do you have an electromechanical, rear limited slip differential, the kind that has internal differential clutches on each side like a "true" LSD except that's it's electrically activated (not the old ABS service brake-applied pseudo system that's been around since at least the MK4)? Even if it does, I don't see how you can check the fluid on each side unless there is a drain plug on each side.
Curiously, there is no schedule "at this time" for a manual transmission.