Given that it would be perfectly legal for the PTBs to promote the least qualified and absurd candidate in exchange for chocolate bars, it's probably just as legal for the PTBs to promote this candidate in exchange for dropping a lawsuit.
And yes, this could be discrimination against the other candidates, but that's legal too. For discrimination to be illegal, it has to be against a protected class. Examples of protected classes include things like race, gender, religion, disability or age. Nothing in your post indicates that the candidates who weren't promoted were discriminated against for reasons like this.

