I don't think software engineers were independently looking at emissions data and unilaterally decided to "fix" the emissions shortcomings in software. I think they were told by others to do that. It's good that Germany is going after the people who decided that fraud was the answer.
> It's good that Germany is going after the people who decided that fraud
When the VW scandal broke, the US indicted seven senior executives. None of these seven were extradited to the US to stand trial [1].
The VW scandal was made public in 2015 [2] and involved cheating since 2009. Sentencing only two executives to jail a decade after their wrong doing made international news does not send a strong message.
[1] https://www.justice.gov/archives/opa/pr/former-ceo-volkswage...
Germany does not extradite its nationals to the US at all. They can sometimes extradite to other EU states, but not to USA.
Sending own citizens to foreign country is generally big deal and not something that is done.