It might generate higher emissions, but whether using it for another year or two generated more emissions overall, I think it's a bit trickier to know if it was worse overall.
Enough VW's not sold mean VW's not built, and producing the car is a large amount of the car's expected lifetime CO2 footprint (I've seen from 1/5th to 1/3rd).
If they were just delaying a less polluting vehicle purchase, a delay is a net negative, but since now they are driving nothing, that means it's actually possible the older vehicle was the better choice, especially since pollution from cars if very front-loaded (if we assume a new car that was purchased would be unused or very lightly used, since they are able to go without a car now).