"We" can easily just mean the universe itself in that phrasing. The Detective Conan series and everything in it still continues because Conan is alive and crimes keep happening for him to solve.
But I feel sorry for poor Genta-kun.*GRAB*We can exist...*SIGH*That's a relief.Thank goodness.It can't be helped, we can't have him going after Conan-kun....because Conan-kun invites incidents to this city.What are you going to do with that Genta?It'll be troublesome if he notices again, so let's lower his intelligence and cause him to be imprecise.