The thing is it seems more similar to the chokorpurr twitch collab, the gong cha collab is not strictly an EU event and is available in NA/EU/JP. Given that it is the second international collab. gives me hope that it does work cross region as the codes could be generic.

I did try contacting NA support through a ticket as I mentioned in original post, but even they did not know the answer....

"We have received and reviewed the request for assistance regarding Gong Cha collaboration, I'm here to check on that for you.

That information has not yet been announced or we are not able to comment at this time."

I have tried contacting them again now that the event has actually been opened and hopefully get a solid answer this time.