Hitler was not killed in 1943. Who then took all the decisions in the next years - which were very Hitler-like decisions -, or who replaced him in radio speeches - the accent is the same and the voice is the same, only deeper and older. Sir Ian Kershaw clearly says in his Hitler biography: "Hitler was not replaceable".
If you don't believe me, check it yourselves. Compare the photos.
Early 1930s.
This photo is - I think - from Vienna in 1938.
1930s as well.
Early 1940s.
1944.
1944-45.
Same eyes, same nose, same ears. Only many years of tiresom upon him. NO ACTOR.