This is gonna sound crazy but what if Terry and Korvo weren't adults when Shlorp exploded? Or maybe they were but they were young adults, young enough that instead of just being them and their replicants they got assigned an adult leader when Shlorp exploded,,, that's why Terry and Korvo both low key suck at their jobs (especially Terry basically knowing nothing about the pupa, Shlorp exploded before he could entirely finish his training)
Also in the what if device when they see what if the button had never been pushed, Terry and Korvo are both acting like teenagers. Terry yelling "I wish I had never been planted" at Zarck and Korvo seemed pissed that he didn't get to be in charge, like he was expecting to be in charge but he wasn't because they put Zarck there.
It would also explain why their team has a 5th member unlike every other team we've been shown
