More Neutral Good than he's comfortable admitting.
Even in his professional life, he administers a guild legitimizing, servicing and protecting fellow halflings, and seems to genuinely believe in the system rather than being a corrupt official.
Most tellingly, the most non-goodly neutral course of action at the very beginning, when they were sent fleeing out of the dungeon destitute and with Farlyn under threat of true death below, was to tell Laius tough luck and look for greener pastures. Namari did exactly that, even when she may have had a small crush on Laius. It was a suicide mission to save an acquaintance, maybe someone Chilchak wasn't even sure he could call a friend, but he followed Laius and Marcille back down all the same.
Of the entire party, and everyone who's gone down there for Farlyn's sake (Laius, Marcille, Senshi and Sureau), the only other person without a strong personal motivation is Senshi, and even he isn't being as charitable as Chilchak, as Senshi already lives in the dungeon and has a nurturing complex from his past trauma. Chilchak's seemingly sole motivation so far is to support his family, and risking his life on a no-profit venture for the sake of an acquaintance jeopardizes that.
tl;dr Mob boss scumlord-looking Chilchak secretly has the kindest and most selfless motivations of the entire party, even if he tries to hide it. I hope he gets his due appreciation in the end.