Like what was being said earlier by Brian, I agree. There are quite a few successful horror pieces that just don’t need Haunt treatments, and some non-horror specific pieces that honestly could work rather well. Fallout the show is a good example and while Orlando’s house was just alright, Hollywood’s was very successful in my opinion.
Haunts work best when there’s strong iconography from a combination of sets, costumes, and characters. When I think back to HHN houses that didn’t work as well, they typically have less of these things. It’s one of the reasons why I’ve never really liked things like traditional slashers at the event (albeit the TCM house at Horror Unleashed is honestly very good). But most of the time with those, you just have the main slashers and then their “kills” for interest, but the sets can be hit or miss. And when you’re getting scared by the same character over and over again it just gets kinda dull. Freaky and Black Phone being combined was very smart and I feel like successful because it combated that issue a bit, but even then those are two properties I personally never would’ve chosen.
That all being said, definitely expect ads going to be playing like you said, maybe a photo area with a back drop, but highly doubtful a character.