Seems like they could just excavate the site and take a look, but then suspense is much more salacious.
I’m a civil engineer and I could tell you stories about things mislabeled on plans or much worse not labeled. Hand dug wells were once very common and once a better source is discover, they are often filled with debris. Working in construction inspection I was with a crew when they dug up a power line (as big as your thigh) to a hydro electric dam, it was an old abandoned power line -thank god. Before it was verified as unmarked and abandoned the power company rep threatened: “Somebody here is getting arrested.”
Clearly, the media is trying to make a lot of the description of a child as “congenital idiot”. What they may well have meant was “congenital mongoloid”. Either way that sounds horrifying by Todays standards, but realize “idiot” and “mongoloid” were once legitimate medical terms. You probably grew up hearing the term “retard”, again this was a legitimate medical term at one time, but it entered the popular lexicon and then became politically incorrect.
Interesting that the people being trashed (in absentia, since they are all now dead) are the only people who attempted to help these children: the women who fed, clothed, educated and cared for them.