@DBB - Rob’s asking those questions posed in Post #18 to this thread for good reason, to wit: everysingle data point goes far in helping our Seller Community successfully steer our ships clear of the ever-rocky confines of The River.
I would submit that neither Rob or I will likely find ourselves in a minority amongst our Seller Community in expecting that anything which you feel comfortable in exposing here in this publicly-visible forum (or elsewise), in regards to the procedure you followed to achieve your positive result, could prove valuable to other members of our Seller Community
I wish I could offer help but I can only offer sympathy and the knowledge that you are not alone. A similar thing happened to me. I sold two different titles from an old (1950s - 1960s) Whitman boys’ series to the same customer. The customer apparently reported me to Amazon for selling counterfeits.
He had come to this determination because one of the books which I had sold him was smaller than the other one and from the other Whitman books he had in his collection from the same series.
In the specific listing descriptions, I had included the dimensions of each of the books and the cover finish (matte or glazed), and since I had created the catalog pages years ago, there was a brief written history of Whitman’s three binding changes in the product details box along with specific series information. When I contacted the customer and explained this to him, he was not convinced. He stood by his expertise in the series because he had other volumes in the series and they were all the same!
My knowledge of the history of the Whitman Publishing Company failed to convince him that he was mistaken. Nor was he impressed by specific references to published works about Whitman series books. He also was not interested in returning the books for a full refund since he was so unhappy!
Of course, I could not produce receipts from the publisher for my vintage books and Amazon was not interested in the references I was able to give to published works which detailed the binding differences either.
The end result, I am locked out of those pages and am unable to list those books anymore. I had created the catalog pages for each of the titles from that series. The product details descriptions were and still are those which I had written. The cover scans used for the main page images were those which I had contributed.
Perhaps I should have continued to fight, but in the end, I just rolled my eyes and listed my remaining stock on another site.