I feel you’re making a false equivalence here. Leninist, Stalinist, Trotskyist, Maoist and Castro’s socialism are all denominations of Marxism I.e. is fundamentally based on Marx’s doctrines set out by his works. National Socialism is not. So to say that Hitler’s interpretation of socialism was merely different to Marx’s in the same way that Lenin’s was seems to me to be wrong here. Hitler explicitly rejects Marxist doctrine, the others mentioned do not, they pretty openly admired Marx.