How to sell a property that won’t perc?

Background: Bought a property in NC, seller said they had a perc test done years ago, stupidly I believed them and closed on it without doing my own. Property just failed the perc for a conventional system because of shallow soil depth. I spoke to the soil scientist who did the test, apparently I've got 12 inches of good soil and then thick clay all over the site. I spoke to a septic engineer who is putting together a report outlining a recommendation for an aerobic spray system. So the lot is buildable, it just needs an alternate system.

I re-listed property, dropped price by $50k (now at my breakeven). Apparently alternate septics are drastically more expensive in NC than in TX. Expensive lesson learned, just want to get out without completely losing my shirt.

I spoke to my agent but he seems incredibly pessimistic about it.

Anyone have any tips for how to sell a lot that doesn't perc?

PS: I know i fucked up and I've learned my lesson, looking for actual solutions if anyones gone through something similar