Actually... You don't get it free...
Thats like if i ask to make a hat and ask if i could get it because i made it...

Sadly, since they accept your idea, it'll be either for a GST shop, a VIP item, a Toy shop, or a free action to all players (Im sure its not gonna be free) at a heaping load of gralats... Just like all ideas were created by others and weren't given anything, the same applies to you. Sorry bro but thats the truth