Youre just outrigh ignoring anything that disproves or challenges your theory that the holocaust never happened. The whole video is him directly addressing a chemistry based argument on zyklon-b and the gas chambers, one made by the very book you yourself posted, and him explaining why the argument you are for is wrong. And this isnt just some random asshole, hes a chemist which is why hes arguing against these chemistry based arguments.

the whole video is this so I dont really know what you want me to do with the "where in the video does he go over it"