Le Baron Noir (the Black Baron) is a very suiting name for a Belgian man of nobility that funded, supported and fomented a fascist underground, which was involved in all kinds of suspicious and criminal activities during the Cold War. It is even more fitting for a Belgian man of nobility that has been directly accused of the abuse and in one case of murder of children by no less than five victim-witnesses. That man is Benoit de Bonvoisin.
Did X1 witness, compelled to murder, Katrien De Cuyper at Castle Kattenhof in 1991? We won't know for sure unless the investigation is reopened with the knowledge of X1's testimony is still credible even though minor details have differed. With all the connections between the people accused by X1 are put into view, it enhances the case rather than discredit it.
All roads in the Dutroux affair, lead to Jean-Michel Nihoul.