Golden Key and cukoo

[Myomoto]

I was wondering why do you get a cukoo instead of a golden key for your clockwork? The icebox gives you a golden key, which leads to the question, where the HECK do you bring the cukoo to get a golden key, because if it's the collector guy at forest that wants it i think it needs to be changed, it's it really on purpose that it is harder to trade with the clockwork than the other quests? ._.