Despite the Soviet news black out, it becomes very clear that they have suffered a catastrophic defeat involving their best units. Rumors swirl that the Germans want a negotiated peace with the allies and are setting up an alternative Russian and Ukrainian governments.
What happens next?
1.) Will the defeat and alternative governments push the USSR to collapse?
2.) Will the allies rush D-Day?
3.) Will the allies negotiate with the Germans, or still force a total victory?
Even accepting all of the rest of your proposed POD, this one little tidbit here is almost pure ASB, unless you have Hitler killed off or incapacitated in some way. Of course in that situation you have a strong chance of either a 'civil war' of sorts as the various factions in Berlin make a grab for power, or you get someone like Himmler running the show. In either case, a negotiated peace won't even be on the table because either a.)there won't be a unified leadership to negotiate with, or b.) whoever is running the show would think that victory is assured.