Cassandra's Trick or Treat quest

Describe the problem. Be as specific as possible!:
Cassandra's Trick or Treat quest:
The level 70 and up version (the one with red candy) only rewards green gummy slime.

After about 7 or so trades of red halloween candy and only green gummy slime, i'm sure it's not working as intended

 Images of problem

I got some other stuff on my Dawn Warrior way back when. The gummies are just really, really common.

The quest is working fine. Like Infection said, though, the Gummy Slimes are almost a guarantee unless you're real lucky.

I saw someone with the Leech transformation the other day, and 2 days ago I got Purple Gummy Slimes and Red ones too.

Oh, it's just that it was such a contrast comparing with the lower level quests. Those ones gave lots of different items pretty easily. The high level one gave me only green gummy slimes so far.