Going back one page from the last, it looks like his old account circa 2011 was terminated, so if it ever was posted there, it's gone now. It'd be neat to find other videos of his in the same style, if they exist, and if he's truly responsible for them.
But here's video proof from some other channel showing that this video did indeed exist under the same "corbettreport" branding:
9/11: A Conspiracy Theory - FringeCraft ReactsFringeCraftDiscord - https://discord.gg/D7F8evanGDTwitch - https://www.twitch.tv/fringecraft*Original Video* 9/...
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