WOW, didn't know that the Morgenthau plan was known by the Nazis.
However, for the germans it still would be the question of "slavery" under the Wallies boot or under the soviets boot.
Not a too difficult choice IMHO.
You seem to think under Totalitarianism the choice was at all in the people's hand.
It was partially in the generals hands, which exactly what they were trying to organize in the West in the run up to the July Plot worked. What do people actually think the goals of the Marshals in France who were all dead by the end of the year by their own hand was? Wait until Berlin is in chaos and order a Lee at Appomattox and turn the war in the West into an uncontested march in.
Where they are wrong is Germany would have not gotten off any better. The ethnic cleansing and division would have still happened, that was why Kluge was ordered to return to Berlin and offed himself first. Obviously, Rommel waited until they gave him an offer he couldn't refuse.
The July Plotters themselves may have been hoping for terms, but the Marshals were a bit more reality based, not entirely though as I am not sure Ike would have even accepted a battlefield surrender in which case they are dead men walking by their own countrymen once again.
The WAllies in many ways were nicer once rationality prevailed among them, but Stalin was more rational in 1944 then the other side (of course he was always cold blooded) a facit of history ignored which is why a lot about what happened in France in 1944 on the German side has been ignored by the historians. Then you would have to answer so would Ike accept a battlefield surrender? No. Ok, let's say he did would the WAllies not have given over Poland and half of Germany to Stalin.
FDR still would have because he trusted Stalin and whats more was convinced he needed Stalin. Churchill was the reality based of the major WAllied nations, but he at this point mortgaged the British Empire to the US in order to stay in the war so America was calling the shots.