Not sure what the controversy is about regarding votes. All the people voting non-Plagueis or non-Valk get the option to tell us who they think wins out of the top 2. So you might be unsure between Mace vs Plagueis but think both are better than Valk, and so when it comes to last two, we see if the majority of the forum really does think Valk is better or if the majority think he's inferior to the runner up.
Valk is actually benefiting from having a dedicated following who will vote for him no matter what, whereas there are some more free-thinkers who consider less common characters like Unuthul who are splitting up Plagueis' potential votes. It was a good rule on Ant's part.