It seems like no matter where I look, Cole gives you the recipe. His events are apparently based on how much you've spent at his place, but I've tried spending over 100k purely crafting weapon, purely crafting armors and even purely buying his shop(reloaded each time, also tried to do a bit of everything), yet I am unable to get the last event, which is apparently only locked behind 15k Cole Spent. Is there another requirements?

EDIT: Seems like you need to craft unique weapons. I crafted all of them but one and I finally got it.