The other review presently on IMDB is by 'ctyankee', presumably saw it in America? That review says "did not like the outcome" - in that one of the principal characters, who helped set up the crime, appears to walk out of Maigret''s office scot-free at the end.
This I think misunderstands the French legal system, in which an examining magistrate would have reviewed the reports, and may have decided to press charges. We don't see this, as the run-time is occupied with Maigret getting into the heads of those involved, and gradually piecing together what must have occurred.
It's a nice episode, more great acting from Gambon, as Maigret, who puts over the brooding thought processes really well (the books make this a real feature, but the TV shows have much less time!), and his own self-doubts with Mme Maigret at the end, when he wonders if he could actually have prevented the 2 deaths. But there's great casting with his team, too, a world-weary Lucas, and Lapointe, who is becoming more street-wise as these 2 series evolve.
That review wonders why one of the criminals is apparently allowed to go free, but the Simenon books quite often have Maigret sympathising with the characters he encounters, in this case a sad lonely woman, getting old but clinging to a young scumbag for company, and allowed (initially, anyway) to plod back out into the Paris suburbs to try and scrape a living.