This is something Brook has been angling after in recent months: to have a "discussion" with a major figure of the so-called "intellectual dark web." Brook's motive is the desire for exposure. The video of this discussion will likely be seen by hundreds of thousands of people; snippets from it may be heard by millions. Without Peterson, a typical OCON video might be watched by a few thousand people. Brook is chasing after views, and with Peterson's help, he'll get them.
However, as the old cliche has it, be careful what you wish for. Brook is playing a dangerous game. Peterson's background as an academic and clinical psychologist makes him a deadly antagonist. He has loads of evidence at his fingertips that can be used against the Objectivist view of human nature. This discussion could easily end badly for Brook. Against Peterson, Brook is way out of his depth.
In her philosophy, Rand denied the existence of innate predispositions of character. This blank slate view essentially renders human nature homogeneous. Human beings, in the Randian view, are, at bottom, more or less alike. If they are in fact different it's because they've chosen different philosophical premises. Since there's no innate predispositions biasing the choice of these premises, there's nothing that would rule out most people choosing Objectivist premises.
Now in his podcast with Gad Saad, Brook took a view that challenges this orthodox position. He admitted the reality of innate predispositions --- possibly a fatal admission (although Brook is too shallow to understand why it's fatal). Brook tried to reconcile this admission to Objectivist orthodoxy by insisting that human beings could get around these predispositions by using "reason." This view of the matter, besides being vague and not terribly compelling, suffers from an enormous defect. Because the question is not whether people can in fact side-step their predispositions by applying "reason," but whether they actually will do such a thing. While it's true that predispositions are not completely deterministic (people can act against them), in practice, many people won't act against them; so that if, as I strongly suspect, the vast majority people are predisposed against many of Objectivism's core views about human nature, ethics, and politics, then it follows that Objectivism will never be accepted by more than a small minority of people.
Despite or perhaps because of the risks Brook is taking by inviting Peterson to OCON, he deserves credit for at least being willing to talk to the Canada's most famous intellectual. When Peikoff was the dominant force at ARI, no one like Peterson would have ever been invited to an Objectivist conference. This suggests a greater openness; but it also betrays a sense of desperation. Objectivism is being crowded out of the public square by people like Peterson, Sam Harris, and Joe Rogan. Having discussions with figures from the "intellectual dark web" is a last-ditch effort to give Objectivism a modicum of exposure and relevance.