Time travel to one of his movies and swap out the fake bullets for real ones and then he'll still be more famous than just a regular movie star but for a different reason.
If you can arrange it to work out just like Brandon Lee's death, you could also save him by ensuring safety standards account for that kind of movie gun accident and we'd have more kung fu movies, too.
It's funny but I do wonder why history got rewritten to make people think that the 3rs Reich did much for space travel.
10k people dead in production, 15k people enslaved, more than 80 USD billion spent, 9 years of production. And the only thing they showed for it was going from a single stage to a two stages. Something some civilian university professors were already messing with. Meanwhile the bulk of "their" ideas were from elsewhere. Using fuel lines to cool, gyroscopes to stabilize, gravity priming...they took all that stuff from spies.
What if all the failed Hitler assignations were time travelers showing up and messing everything up, and the one person that was successful made it look like suicide.
Hitler's destiny is already killing himself while malding and shitting himself, which is a miserable enough way to die. Lots of other assholes died quietly in bed though.