Things will obviously be different on Gotham, which doesn’t have a Harley Quinn, and it doesn’t seem like Barbara will take that title.
In any case, though, the point is that this corpse is missing his face skin, and that’s exactly the kind of grisly shit that Gotham excels at.
Plus, it’s more likely that Jerome’s return will have something to do with Hugo Strange’s experiments that brought so many others back from their deaths.
Perhaps he’ll also get some of Alice Tetch’s blood.