http://www.wowhead.com/quest=29517/eyes-on-the-prizes
Adding this made it work.
[29517] = 823,

Another quest I found, which could work better, is:
http://www.wowhead.com/quest=26572/a-golden-opportunity

The knife comes up okay but once you cut off the tail it stays as the knife and you've got to go digging through your bag for the tail. It would be awesome if the button would swap to the tail when you got it.
http://www.wowhead.com/item=58958/drowned-thunder-lizard-tail

Not sure if that's possible, just mentioning it in case it isn't too hard. :-)

Priorities aren't that easy sadly, would require a bit of extra work to make it happen.
Normally quests get rid of the previous item, but apparently not in this case.