The reading was very good, though I think if there had been many more voices, it would've gone gimmicky.
The story was interesting at first, but I think it fell upon a few too many fantasy tropes: king lies about great deed to become king, king's grand vizier (the old dude in the robe and slippers) tells hero to lie, hero is king's illegitimate child (most likely; it's never actually SAID), hero is very intelligent but not necessarily gifted with a sword, hero's trek to proving ground is annoying without being actually difficult (drudgery more than anything).
I didn't have any problem with the underlying reason for the dragon wanting to die or how he got to that point, but I think it was too easy for Kim to come to the point where he was ready to do as the dragon wished. Sure, he'd immersed himself in dragon lore, but when a bloody great lizard pins you to the mud with a claw, you probably aren't going to be willing to just sit there and talk to it no matter how much you love the idea. Maybe it's just me, but even in a fantasy world that doesn't seem realistic.
Also, though the story was from Kim's third-person POV, I really needed more to believe that he'd just kill the dragon and then leave the kingdom. The story wrapped up too quickly. I almost feel as though the dragon needed to ingratiate itself more to Kim, to bring Kim around to the idea. The dude loves dragons; he's just going to kill the last one in the kingdom (despite what it said about there being more out there somewhere) after talking to it for one day?
I don't necessarily want the story to have been longer, but I wanted more interaction between the dragon and Kim. That's where I think the story fell down.