Per https://phabricator.wikimedia.org/T292954#7469436:

Just noting that I had a lot of trouble uploading a large file: y2commons didn't work, ChunkedUpload didn't work, publishing from my stash didn't work (a half-dozen times), and one last try at ChunkedUpload/stash failed so badly that the special page for my stash wouldn't load. I have no clue what is up. Another user helped me by uploading the file to en.wp but it needs to be ported over to Commons and overwrite the malformed version there: https://en.wikipedia.org/wiki/File:David_Pakman_talks_to_Rebel_Wisdom_about_politics_and_media.webm

Can anyone do that?