That is specious reasoning and you should be ashamed to dabble in it yourself, quite frankly. We have NO WAY of knowing whether or not the Nazis would have refrained from the Holocaust if the war had not started - however, they gave clear indication that they would like to go that way before the war. Take this crap elsewhere.
It's not just specious reasoning - it is deliberate unreason.
The second the Wehrmacht rolled through Poland they were followed by Reinhardt Heydrich's Einsatzgruppen.
An intentional policy of mass murder was not only contemplated but in active performance literally from day one.