First I want to say that being on a list of war crime suspects - which is what the list is likely to be - doesn't necessarily mean that one actually committed war crimes.

You could try and write an email to this German office which investigates Nazi crimes and supply them with the name and other relevant details which would help them to identify this person in their files.

https://zentrale-stelle-ludwigsburg.justiz-bw.de/pb/,Lde/Startseite/Kontakt

Of course, if they don't find his name won't mean that he is innocent, but it's a start.