There are plenty of older documentaries, mostly mainstream posted on Youtube about this case. Here are a couple to view, one by an influencer, the other a mainstream media with interviews, dubbed in English.
The BELGIAN DEMON - Marc Dutroux
The Marc Dutroux Pedophile Ring: Government Officials, Murder & Satanic Sacrifices (VERY DISTURBING)
Down voters, you all can keep feeling outraged over 3 different things a day, I’m out.