It does say what was said in the original. Here is the original. https://x.com/upholdreality/status/1912954706739269991
It seems to just be one of those AI that makes foreign language sound and video seem as though it was actually done in English. So that is why it says it is dubbed and the visual lines up with the audio.
Open box might be tempting!
My Paperwhite is also the 2015 model. Not seeing individual pixels with a magnifying glass is awesome to hear. I certainly think that it would look good for manga or other black and white format comics.