it is 02 sensors but you could run 44k through it a couple fill ups, or what i found that the 02 sensor wires were hanging around exhaust and heating up enough to cause 02 sensor to fault. pulled wires out replaced with a brass wire not like the silver wire they use then after dropping wires back down make sure you put the wires away from exhaust, tuck them behind heat shield if you can. but after i did that my 02 sensors did not fault anymore i believe that the wires where not put in correct place when the 02 sensors where replaced to begin with. before i owned the car thanks to that mechanic. but the 02 wires that not being brass that where on there seams stupid not a good conducting wire, that's why i use brass to preserve the signal strength.
I am not aware of an emissions "workshop" light in any car but I never drove a VW either except 35 years ago when I was taking drivers ed class in REAL CARS and going up a hill in a beetle I floored it to keep the speed up but coming back down the hill I found the accelerator stuck to the floor and by the time we all were doing 80 mph in a 45 zone did my instructor freak and reached down to his floor peddle and pull up real hard. We took it to a shop and got a taxi back to school.
I am sorry for rambling but I think that you may have a problem with your exhaust system. Could even be something to do with air pressure in your emissions hoses. Heck it could even be as simple as replacing your gas cap. Either way take it to your nearest VW mechanic and have it checked. Unless you have to pass an emissions test to get renewed tags or if not and nothing else seems to be running badly then you may be able to keep driving and enjoy knowing that "idiot lights" some times don't mean as much as they pronounce them selves to be. Any hesitation on your part means the mechanic now.