That ground penetrating radar really delivers but what is the stunning part?
Finding 12 ancient skeletons in a place that was not previously known as a tomb is pretty stunning. Imagine if you found 12 bodies under your neighborhood bank- people would freak out, and it's not nearly as old as the Petra Treasury.
Many places we know now as tombs weren't known as such before, that is untill some skeletons were found.
If you wait around long enough anywhere becomes a tomb.