Actually, Sleeze didnt even die until many years later did he? I remember seeing him show up in The Ray, and I think he was in Death of the New Gods too, though I didnt read that so I could be wrong.
Odds are Zatanna magic'd all those pornos out of existence. I mean, she mindwiped a dozen or so villains (at least) as well as Batman. I can see Superman taking her aside after a League meeting and being all "So, I need to ask a favor...."
"We all know the truth: more connects us than separates us. But in times of crisis the wise build bridges, while the foolish build barriers. We must find a way to look after one another, as if we were one single tribe."
~ Black Panther.