I don't know any better than anyone else precisely what Jennings is alluding to.
But given the subject matter - Biden's appearance on The View yesterday - it sounds to me like he's probably referencing the audio of Biden's testimony in the Hunter investigation.
And, if that is indeed the case?
Watch out:
That may not only be an epic explosion to the very edifice of the Democratic party, it would also take the legacy media (even further) down with it.
Popcorn, booze, and the big screen are all highly advised.