There is no behind the scenes drama, folks. Ridley Scott and Neill Blomkamp are professionals. It's not RS being a tyrant and using his power to cancel another film. It's a business, that's just how things work out.
Perhaps if Neill Blomkamp got his timing a little better then this whole thing would not have happened. He should have at least consulted with Scott before pitching to the studio. Not assigning any blame, but this whole mess could have been avoided.