When the two of them SHOULD have been popping up to help each other (or at least been in each other's stories) since the breakup. Like, everything they've been doing with Owens and Zayn since really KO joined NXT (i.e. telling a long-game story that they periodically check in on but don't have to focus on) was what they could have been doing with the Shield. And it would have gone a long way.