Apparently, Disillusioned Adventurers Will Save the World Novel Volume 2 is written by Shinta Fuji.

Betrayed and kicked out of his adventurer party, Nick thought he might never trust another again. However, it isn't long before he finds new comrades with similar experiences: Tiana, a mage and former noble lady, Zem, an excommunicated priest, and Karan, a female dragonian warrior. Together, they form an adventurer party called “Survivors” and are later joined by the Sword of Bonds. But just as things start picking up for them, Nick runs into his ex, Claudine, and they get dragged into a duel with her adventurer party. Can the newly formed Survivors win against a group active in the underworld?