He's not read it cover to cover, but he knows full well what he's signed up for. AJ and his parents did a TON of due diligence, and they've been on campus a bunch of times (at least four visits for AJ's parents, or at least his dad, and at least three visit for AJ). AJ has hung out with the team, attended a couple basketball games, etc. BYU's unique culture is one of the big reasons AJ chose to come to BYU.
Let's also keep in mind that AJ is living in small-town Utah right now.
And, you KNOW every other basketball program that we were recruiting against had lots of lovely things to say about the honor code. I imagine AJ heard a lot of garbage about BYU along the way. But AJ still chose to come to BYU.