When I look at the page of the
Mercedes C43 AMG they state a fuel consumption of 9.3 - 9.1 l/100 KM which corresponds to a combined CO2 emissions of 213 - 209 g/KM.
This means that they have also taken into account a weight of more or less 2 293 grammes of CO2/liter of petrol.
In my first post I mentioned that when comparing the different models it seems that BMW uses a weight of somewhere between 2 273 and 2 293 grammes of CO2/liter of petrol.
If we assume that the actual formula should take into account a weight of 2 293 grammes CO2/liter of petrol and under the assumption that the G80 will actually have a fuel consumption of 8.9 l/100 KM this means that the CO2 emissions will be closer to 204 g/KM.
Formula
8.9 l/100 KM * 2 293 / 100 = 204.077 g/KM
One thing is clear: the G80 will be an amazing car