It’s like saying that historians lost track of the site of the Crystal Palace in London or of the Vanderbilt mansion on New York’s Fifth Avenue.
BUild Back Better ! ( sarc.)
Not really. Everyone knew where the building was. What they didn’t know was where some interesting rubble from it was dumped, like a Ten Commandments in stone, some columns etc. Now that those items have been found they can use them for a monument or something.
It wasn’t that they didn’t know the original location where the building has been.