The boring and unsellable Shakur is certainly the huge favorite even if he won't probably hurt Joe.
It's fitting that his fight is on the undercard rather than the main event, as it tends to be boring. I'd even prefer it if he were the third fight before the main event, so the audience still has energy left. If the crowd gets bored, they might not enjoy the main event as much—just kidding.
But seriously, fighters like him don't bring much excitement unless there's someone who can counter their strategy and beat them. For example, the fight between Ryan Garcia and Haney was entertaining, even though Garcia won, and it was later ruled a no contest. Despite that, the actual fight was still enjoyable.
He could be in the 3rd card on this fight though, but not sure why he made him in the second fight before the main card, we all know that Shakur is a boring fight, his style and not something that fans appreciated and maybe his personality too, somewhat brandish but he doesn't step up in the fight and just picking a fighter that he will beat, but can't knockout.
As if he really holds back something and doesn't want to take that risk, unlike other boxers when they go up in the ring, they wanted to give the fans a good fight and worth our money on buying and seeing him fight live.