You wrote that the seller said "Basically he says the auctions would never give details to anyone. They never do it, it's against policy."
And, "That's just how it is they have rules, you never know the lady may have died & it may be her children who consigned it. It could have been found in her belongings, there are a thousand reasons why it may have been put there; we will never know."
Is he even answering the question you asked? Why can't you even know which auction house it was? How(why) is seller "protecting himself" as you say he said, by refusing to say even what auction house it was from?
It still concerns me that the addresses and info on those photocopied auction "proof" papers was crossed out in ink by the seller. That prevents you from easily confirming the signature was connected to the copy auction papers. He won't even tell you what auction house? And the exorbitant fee he was saying you'd have to pay to return - $180 to send a slip of paper to the UK? I do not often listen to everything sellers say, but some thing stick out. You could ask the room about his behavior. You said you thought he was trying to rip your brother off. I suspect for many collectors, this would be enough to warrant a return of most anything. His behavior seems very unusual to me. I'd like to know why. I would post this information in your Jones thread and see what other collectors think - ask how they might react to such information.
I saw your comment - 52 years old is your oldest. Which autograph is that? I would have to think about my answer - offhand I know my signed log from Mauritania's Captain is 1906...signed Nelson Dawson lithograph 1914...my earliest photographs are signed 1906 so that's probably about it. I think...