I think it’s more important that the U.N. deal with things like the fallout from Trump’s misguided decision about Jerusalem, famine and a long list of things I’d imagine. Dealing with a computer game company would really be a waste of their time and resources...
P.S. If you have a child and you think he/her is playing a game with similar traits to gambling in it then it is up to you as a parent to take that product away from said child. It’s called good parenting...