I have not had my first oil change yet on my 2015 - so this is a preliminary question.
If the wire that is left disconnected during the oil change, (I believe it is the electronic water pump), will it set off the MIL/engine-light on the dash?
If yes that is a good thing because you will know the tech forget to plug it back in,
If it does not set off the engine light, then the only way to find out is: the hard way - overheating engine - or by crawling under the car and checking it.
Pick your poison:
1) Express service lanes at the VW dealer: for oil change, tire rotate - is usually done by an "on spot trained" teenager or young fella trying to move on to be a certified tech.
That is all they do all day long so they should have the steps memorized.
2) oil change done by a regular service tech: he is capable of performing all works on a VW, and an oil change is easy for him, but likely wants to get it out of the way quickly so he can move onto other better paying services.
when I worked for General motors- we only got paid 0.3 hours for oil changes (18 minutes)- this included locating the car in the parking lot, driving to the service bay, get the parts from parts dept, do the oil change, tire pressure, fill fluids- and other mandated inspections to upsell work such as check brakes (sometimes pull the wheels), tire thread dept, hoses, belts, air filter, lights -then record all findings, park the car. Regular techs (paid by booked hours) hate oil changes unless it turns into an upsell.