When the movie came out, Billy Mitchell claimed the tournament in Florida was edited to make him look bad.

Specifically, Billy had been conspicuously avoiding playing Steve in a head-to-head matchup in Donkey Kong, afraid he'd lose. When Billy does appear, he walks by, ignores Billy's greeting, then whispers to his wife, "There are some people I don't want to spend too much time with."

Here's the accusation from Billy and the rebuttal from one of the producers, Ed Cunningham:

https://film.avclub.com/the-king-of-kong-continued-donkey-ko...

"Ed Cunningham: Yeah, no, that didn't happen there. It didn't. At that moment, what we show is exactly what happened."

Yes, criticized by the person who has been exposed as a fraud and lost all credibility in the gaming community.

A.k.a. the subject of the article.

There are many things that can be disputed without having to believe a word he says.

For instance they played head to head at an arcade a year before the documentary started filming.