I am confused since it seems like there are two issues here. The elder's first question seemed to be about whether repentance should prevent DF'ing of a child molester. But then it seems like the real discussion was about what to do when there is arguably not enough proof of whether the abuse took place.
It seems obvious that the answer to the second question should be to alert the authorities and let them do a real investigation and warn the accused not to be in the presence of any children in the meantime.