I have a small parcel of land for sale in southwest Colorado. Last year, a woman from Las Vegas offered on the parcel, we were under contract, then she and her broker failed to show at closing, offering no explanation. The contract terminated, of course, and I kept half of her earnest money. Six months later, I had another buyer under contract when an engineering report from a firm this woman “hired” after my contract with her terminated surfaced two weeks before that closing. To be ethical, my broker and I decided to disclose the report, which mildly suggested the parcel might need extra foundation work before it could be built on. Nevertheless, the buyer walked and we have since determined the report is bogus. Since it was apparently done vindictively and not done as part of due diligence under contract, do I have to disclose it in the future?