“Draco, being a clumsy sort of wizard, accidentally dismantled all of the tomb’s wards, and tripped over, and pushed off the enormous marble slab that covered the grave. Then the Elder Wand fell, quite by chance, into Granger’s hand, and she, out of sheer ineptitude, created a perfect duplicate of it, and, by absolute happenstance, dropped the duplicate into the tomb, and they left with the Elder Wand in her pocket without noticing that it had fallen in.”