I'm going to go one step further and say that adding Zoey back into the mix so late in the game was a total waste of time.
Zoey's reappearance in the game certainly upsets the equilibrium or at least distracts us from what we'd hoped would be smooth sailing with our chosen LI at the end of episode 8. However, we're not really "late in the game at all," assuming that DPC still has at least two full seasons left of BaDIK to tell. We are halfway through at most, which is exactly when one would expect a new conflict to emerge in any good story. Assuming DPC knows where this story is going (and there is every indication that he does) this is a very deliberate introduction of a new (old) character in order to generate new conflicts and choices. Time will tell whether this is successful or not, but I doubt that her presence is simply "padding" for the game or some other form of superfluous content.
From a game design standpoint, too, Zoey's reintroduction makes sense, as every MC (regardless of his DIK or CHICK choices, etc.) was Zoey's boyfriend and lost his virginity to her (even for players doing a celibate run, their MCs are not virgins), so DPC won't have to deal with so many variables.