No, his Luck was always destined to be shared with whoever would become his wife. The game was just meant to facilitate that happening and securing the heroine's spot as his future spouse.
It wasn't fully automated, she could create events and change rules and such on the fly. So it was more so that it was only partially automated. Overall though, it was still tied to her magic so if she loses power then the app should die down too. Realistically though, Zepa shouldn't have lost though. The entire thing was tied directly to Asunaro's feelings, there's no reason why he should've been able to fake those feelings (to a magic app) let alone weaponize them at the end. Also it makes no sense that another heroine could be added when it was specifically made to be a game for him and for his crushes at the time and no one else. What if he got a crush on someone else during the time this whole thing took place? Or he keeps crushing because he realizes he can just have an infinite harem. It's one of those things you'd easily figure out is problematic from just thinking about it a bit. It's a rushed ending, clearly, but it's what we got.
My head canon is that Zepa faked this last chapter. She faked being defeated and cancelled everything just to get Asunaro and the girls the best ending.