Even if he experiences a recovery period, he could still be angry at Jews over "the deluge"--as in, the period of his life where he was stuck in East Prussia and completely powerless and non-influential over the rest of Germany.
With the German Kaiser remaining in power, it could be harder for Hitler to implement his atrocities. Or maybe not consider that Kaiser Bill already talked about gassing Jews back in 1919 :(:
https://reviews.history.ac.uk/review/47
Without East Prussia, I wonder if Wilhelm Marx wins the 1925 German Presidential election. If so, this should give Weimar democracy a huge shot in the arm.