1. Hitler's death was not enough. To succeed the coup had to kill or neutralize Hitler, Himmler, Goering, Borman, and Goebbels.

Assume that they did.

2. Germany is now headed by a half-military/half-civilian junta. The Holocaust is happening on autopilot until countermanded. The Soviets are attacking. The Western Allies have taken Rome and are established in a bridgehead in Normandy. Germany sues for peace.

The Russians say no and continue -- which they will do regardless. They have no interest in stopping short of the Elbe and probably would have preferred to get to the Rhine. The Western Allies honor their alliance with the Soviets -- however grudgingly. The War continues and we end up with the same partition (though the Holocaust is quickly curtailed and some of the stupider "hold and die" orders are never given.

But suppose the West did make a separate peace (however unlikely).

3. The Russians get to the Rhine. Sorry PJ, but der Wermacht is a shell of what it was by this point. It is the Soviets who are punching holes with armored spearheads while the Germans use hastily trained conscripts and kampfgruppe "fire brigades" to stop them as best they can. German industry, revamped by Speer, is up to the task (especially if the Western Allies are not involved anymore) but the Germans simply do not have the time to train people or enough experienced cadre to use all the new wonders that had been cooked up. Moreover, the remaining elite formations are very likely being broken up by the new German government which cannot afford groups of SS troops or Luftwaffe troops of dubious loyalty to the new government. So maybe JV-44 sets an all time record for kills and we see that in competent hands the Jadgtiger really could knock out a JS-III, but it is still too little too late. The Soviets bleed a lot more, but they still get to the Rhine (or to the split line between them and the West).