But those acts weren't known until the end of the war. It was the Invasion of Poland that kicked everything off. Yes, Hitler and The Nazis were known for their anti-semitism, but they didn't know to what extent. When the Holocaust was first brought up, it was dismissed as propaganda.
I certainly agree, hell even in Germany information was hard to come by and often what you heard you didn't know if it was true, Allied propaganda or falsehoods spread by the secret police to 'test your loyalty'.
But, when I say changes to the timeline could mean there is a war, genocidal actions, but no Holocaust as we know it what I mean is you could have a World War 2 without Hitler and Himmler running Germany, or with them running Germany and doing much worse militarily then OTL so they have either been defeated by early 1942 when the Final Solution was enacted or focused far more at the armies at Germany's doorstep then on what to do with the Jews and others.
By the same token in a Germany victory [in the East] timeline. Hitler and Himmler could be so busy and focused on killing Slavs and getting the East set for future German colonization that they decide to use the Jews as slave labor and stick them in some hellhole in their vast Empire. In that case there would be an even bigger slaughter then our history books record, but it wouldn't look quite like the Holocaust as its known OTL.