I think the MK5 has electrical gremelins.
I've had the rear wiper go on and stay on until restart... countless others have too.
I've had the drivers window descend when requesting it to ascend (no error codes).
I recently swapped the switches out to chrome ones and have a central locking fault code?
I liken it to computer programming; you may find a whole load of errors flagging up, yet it will be 1 underlying issue then all is resolved.
If I was you,
I'd get the car scanned, it may flag up some area which isn't obvious.
However, FYII it could well be your switch, the terminals are known for fouling (my cruise control did), you can split the stalk apart with your finger nails and pop the PCB out and clean (assuming it's the same as the cruise stalk)... worth a shot.
Or does a new wiper motor need to be coded in? Either way, get someone with VCDS to give it the once over.