Hitler's rise to power was hardly inevitable even in 1933, the nazis never broke 50% of the vote and his coming to power was because of backroom deals made with Hindenburg to appoint him chancellor, all the while convincing the nationalists and other right-wing parties that he would be the "junior partner" in a right-wing coalition.
In reality, the Nazi's electoral numbers were -falling- from election to election by the time Hitler was appointed and the party was running out of money and in all likelihood would have suffered big electoral defeats in the coming months and years. The depression was getting less severe and the Republik was likely to have survived if Hindenburg held firm.
So let's say Hindenburg ATL is somewhat healthier and clearer of mind, while the right-wing nationalists are more wary of Hitler, he does not get appointed chancellor in early 1933, what happen next?