There seems to be a limit to how many times you can repeat this quest in short periods of time. If you cannot get a new quest before moving on to the master quest, you will need to wait before you can repeat it again.
Cornail will at this point say "I have nothing more for you at this moment. Return to me after I've had some more time to assess the local threats."
This quest does not scale, but does have three stages. Each stage must be completed 10 times before moving on to the next.
You have to do each stage 10 times before you gain access to the next stage. IE.. Finish the level 32 version 10 times, then you gain access to the level 36 version. Finish the level 36 version 10 times then you gain access to the level 40 version.
Slay a number of Orcs in Zek, randomly assigned from this list (there is a cool-down timer of 60 minutes from completion to when Cornail will offer the quest again - deleting to get a different version didn't seem to be a problem though, so if you do not like your mob, you may delete the quest and get it again):