leading the Nazi program down the wrong path. There is question as to if he knew it was the wrong path, or not. Given enough time, resources and smart minds, Heisenberg could have found a way to a viable Atomic Bomb. The path he was on until the end of the war would not have gotten him there. There wasn't enough critical scientific mind mass in the German effort to get there. The US had it, and once it was done the Russians were able to follow (with some espionage aid) to follow suit a few years later. The fundamental science is such that your average High School Physics Student can understand it - but the manufacturing and engineering tolerances are still today only something that is only achievable at great expense and effort - and only with the roadmap provided initially by the US efforts.

In a "Man in the High Castle" sort of way, yes Germany could have gotten the Atom Bomb before the US - but it requires so very many changes in the disposition of the smartest physicists, engineers, and machinists on the planet, in addition to finding a way for a struggling German economy to fund the effort - that it was in the actual history to have not been anywhere near a close-run thing (though during the war it was difficult to ascertain how far behind Germany really was).