An excellent movie, very exciting, riveting actually.
However the entire plot falls flat. If an Allied victory is only days away, perhaps one day away, there would be no need to steal the art masterpieces.
If Germany was indeed defeated at this point then the paintings would have to be returned to France eventually.
At this point evacuation of German forces should have been the first, priority, to defend the Fatherland itself, to protect Berlin, to wrangle at least minor advantage in the ultimate peace settlement.
At best Germany could declare a unilateral cease fire, and hope for the best.
Form a new government to sue for peace. Spare their own people additional suffering.