This is extremely simplistic and reductive, but essentially, after JD Vance was named Trump’s VP, someone made a shit post saying ‘Wow, I can’t believe he said he had sex with a couch, that’s wild’. To their slight credit, the same person commented like an hour later admiting it was all a lie (they just posted the Arthur meme of “You think someone would do that? Go on the internet and tell lies?”), but that didn’t really matter and it got shared around a lot, mostly by people who knew it was fake news but still thought it was funny anyway.
Later that week, AP News did a fact check on it (because, sadly, they have to do A LOT of false-fact debunking) and they essentially said “JD Vance did not have sex with a couch”. HOWEVER, they have an internal policy that says their fact-checks must say only the truth, even if they have to be extremely specific in their wording. Since they originally said “No, he has never had sex with a couch” but, technically speaking, unless they’ve been spying on him for his entire life, there’s no way to actually PROVE that, so they had to take it down. Lots of people saw it get taken down and jumped on that fact as a ‘Well, then he must have done it, obviously’ and the memes continued.
Fast forward to today, and some FOX host who probably still uses Yahoo as their search engine and has no connection with meme culture is demanding the video proof that they presume to exist despite no one EVER saying that there’s proof.