Some mixed feelings on this chapter... I am, first of all, glad to see Laermont in a more active role. I didn't necessarily mean that he needed to start fighting when I called for that, but I do like seeing that he can hold his own in a scuffle. The fact that he's actively investigating and calling out TorBru immediately reinforces that he's a protagonist in your story.
I do, however, have a few concerns: Lupanar District is dangerous for law enforcement. When Laermont makes the threat to escort his prisoner openly, it's actually Laermont who would have gotten in trouble, and he likely would not have made it out of the Little City. By keeping the arrest discrete, he avoided drawing attention to himself. We can chalk this up to the thug not being up and up on that, but most regulars of the district would be cocky in that situation, and promising that he'll never make it out of Lupanar.
Remember, it's basically under its own rules, enforced by the criminal organizations there.
One other detail: you wrote Guadriar the Red, but given the context, it would be another member of the NIN, Artemis Culpeper, who would meet with Mercuti. Guadriar is the man in charge of the NIN -- which isn't the entire Nefastus, but a significant group within it -- and he's unlikely to leave the safety of Lupanar. Artemis handles brokering information to and from industrial leaders in Terminus, and is the one with ties to TorBru. The nature of their business would also be information or misinformation, not protection.
As I said, though, I'm glad to see this more active element. TorBru is trying to cover their tracks, Laermont is trying to pin them down, and now there's a personal element to explain why they're going after Laermont so doggedly. He's just boldly strode into Mercuti's office to confront him. Not only is their business riding on Laermont being silenced, now there's a pride aspect for Mercuti, too.