Feel yourself free to link and quote Dubay, 2008.
Looking up his literature list, he's in flat earth not before 2015.
You're making the allegation. Where's your proof ... other than what you pulled from the recesses of your posterior?
I already linked to his first book in 2008 with a flat earth picture on the cover, and the 2009 (The Atlantaean Conspiracy) in which he devoted a chapter. He contacted Alex Jones, and there's video of Alex Jones ridiculing him (I think it was 2010), where he says "Some Flat Earthers even tried to contact me. Flat Earth is ridiculous. But even they contacted me, claiming it was part of some kind of Atlantean conspiracy (the name of Dubay's book published in 2009).
Explain then, within the paradigm of your theory (completely made up), why Jewtube deleted his channel twice and why Big Tech are censoring search results on Flat Earth.