Neither were the people in Germany.

The court sent the former head of diesel engine development behind bars for four years and six months, and the former head of powertrain electronics to two years and seven months. Two others — Volkswagen’s former development director and a former department head — received suspended sentences, according to Der Spiegel and Deutsche Welle reports from the Braunschweig courtroom.

The (now ex-) CEO of VW, Winterkorn, is a fugitive from justice in US – the reason he isn’t in prison in the US is because he’s hiding in Germany, and Germany doesn’t extradite its nationals. IIRC from memory back during the incident, he’s facing a total of over two hundred years in potential sentence from the charges, though some of that would probably run in parallel, were he convicted, and I assume that in practice, there’d be some sort of plea deal.

EDIT: Maybe it was over one hundred, not two hundred. I distinctly remember trying to figure out whether the sentences could run in parallel when reading an article about it at the time. In practice, he’d probably plea bargain it down, but there also is no parole for federal sentences in the US, so he wouldn’t be getting out early, either.

EDIT2: Also, because he’s a fugitive and it’s a federal crime:

https://www.law.cornell.edu/uscode/text/18/3290

18 U.S. Code § 3290 - Fugitives from justice

No statute of limitations shall extend to any person fleeing from justice.

So I expect that he’s probably going to stay in Germany for the rest of his life, unless he can find some other location that wouldn’t extradite him (Russia?)