The National Archives was doing an audit of classified documents connected to the Obama Administration. Someone started noticing that a whole bunch of documents that were checked out to the VP's office were never returned. The National Archives notified the White House attorney about the missing documents. The White House attorney told Uncle Joe. Everyone flew into a panic. In order to prevent the White House attorney from having to testify as to what took place, she quit government service. She is now Uncle Joe's personal attorney and thus can't be made to testify against Uncle Joe. Since so many people were aware of what was going on there was no choice but for Uncle Joe to fess up. They sent a team of attorneys to clean locations of classified documents so no one would send the FBI.
You will note that at only one location was the number of documents found mentioned. The other locations exposed so far don't mention how many documents. I bet there is a ton of classified information that has been found and is being covered up.
It may well have happened as you described.
However, my hunch is that the discovered documents never were sent to the national archives because they relate to the illegal and fraudulent activities of Biden and other Americans in the Ukraine throughout his tenure as Veep. Biden people wanted to maintain control of them.
And, I suspect they were discovered at the urging of deep state operatives because they are finished with Biden and ready to move on.