Here are the drama CDs that came with volumes 17, 18, 20 and 21 covering the Forthorthe arc, set right after the anime ended.
I translated the last three, I’m not brilliant at translating by ear so there may be mistakes in those, I’ve used some lines from the LN translation.

The first one was translated by AbyssMatuk on YouTube, but I included it for completeness’ sake.

Thanks to my ISP, my upload speed is pretty bad, so if anyone that can download from MEGA and help seed would do so, I’d appreciate it.

If you don’t want to download them, all four are on YouTube