The Braunschweig prosecutor's office says the amount of money in question is "not insignificant." It is focusing its probe on five individuals at Volkswagen, but hasn't named them. This is a brand new probe because it has nothing to do with the diesel emissions cheat software and the personnel involved in that - it is a new matter with new players.
Volkswagen says it has put aside two billion euros ($2.1B US) for to deal with the CO2 issue, separate from the seven billion euros ($7.4B) it has put aside for the diesel affair. That money would pay the balance of taxes that were originally due, and penalties. It could also be used to reimburse owners of the models in question for the extra taxes they need to pay for higher CO2 emissions. There'll be no fixing the environmental impact, however, since unlike diesel engines and their NOx emissions, rated CO2 numbers can't be fixed after the fact.
VW's global headquarters are located in Wolfsburg, Germany, not far from the city of Braunschweig.