The theory the bodies were violators of social customs, are not something Nazi-specific, it is a common hypothesis. They are clearly ritualistic executions, and it corresponds to Tacitus which states that "traitors", "cowards" etc. were hanged and then buried in the bogs. So given how little we know overall, it is actually a pretty well supported hypothesis, since archeological and historical evidence match up.
That Nazis used the theory does not in itself make the theory suspect.