I couldn't "win" the Chrysanthemum dragon, either. I bought the value pack with the Sweet Pea dragon and enough points/hearts/whatever they were called this event that I could get it on one account. My other two accounts barely got the first dragon, but, hey, at least they got one new dragon each and all the community prizes.
Speaking of prizes, so even though my 3rd account isn't high enough to use marble keys, it is letting me have them from events and then store them until I need them. Why doesn't that also happen with Island Parts that we get from Storybooks?