First, in NT the assessor of wit has an odd bug. If I get the riddle, go into town and buy the answer from the assistant, then talk to another NPC in town and accept a quest, I also get a message from the assessor that I had the right answer, and he gives me the next riddle.
Second, in Kion, the guy that gives the quest that has Howling in the name, I think he is the town marshall maybe, the quest completes right away and I can turn it in. Multiple times, actually.