I did something simillar on the last table i DM, i created a village where the players found when they are looking for a "kidnapped" daughter of a Duke, the girl and his boyfriend got captured by a group of bug man who took over the place.

The discovered a giant underground nest where the bugs are hidden because the valley where used to be they home was taked by the settles and they build the village, than they fleed to the underground and keep hidden until they took back the place and disguised themselves as settlers.

The rogue get a critical success on the roll and infiltrated on the queen nest, guide the rest of the group on it, and with the help of the half djinn mage they persuaded the queen to free the girl and her boyfriend, promissed keep their secret and and the paladin even got a chitin heavy armor on that.

I'm glad they opted for the pacifist solution and keep they word on the promisse...