But VWs debt is mostly due to them operating as a bank that sells loans to their customers to buy their cars. So it's more nuanced than just folding the into the calculation. Most other car manufactures don't do that directly.
Point is that in broad strokes it doesn't add up.
Regarding the "operating as a bank", are we talking about net debt? I'd guess that if VW loaned money to customers those loans would be assets, right? They wouldn't get the cash from the customer, but they'd get something that looks about as good for their balance sheet hopefully?
Unfortunately the standard ratios only subtract cash from debt when doing this calculation so this calculation is one you have to do manually if you want to fairly compare car companies.