I actually would like to see that. BUT. Bill is much smarter than Collector and doesn't have his child innocence. Also, it wasn't shown if breaking deal with Bill has some consequences (for example, what if Bill gave Gideon code and then Gideon refuse to do his part of deal). Belos should be pretty smart to understand what that deal would be dangerous to him. Also, i doubt that Belos would like to help Bill spread chaos across world. He is maybe Pure Evil but, unlike Bill, he doesn't want to watch world burn.
