Although your colleague might appear a bit unreliable I see no reason why she would conceal any possible observation of intrahepatic gallstones.
Plus, it is completely irrelevant whether she is trained or not in the field of medicine. If the liver holds the stones it is reputed to hold, a senile old granny could cut a liver in half and notice them. Yes, as everyone keeps repeating, they are in the bile ducts, but if you are DISECTING the liver then you should be exposing those things in all their glory. But no, invariably all anyone sees is a load of liver tissue and clear ducts with absolutely nothing clogging them up.
Only the "believers" see them I suppose. In that sense, those naysayers who compare flushing advocates to a religious cult are not far wrong.