Regarding point "b)", I think you made your own point against yourself already: for most people, the scene is 100% different since they don't understand German. If I were to make a parody where I changed the words, I don't think it would be a valid argument to say "but for deaf people the scene is exactly the same!". Similarly, keeping the music and doing drastic changes to the visual you could argue "but to blind people its exactly the same!".