I wouldnt be that over zealous to prove anything, unless you feel to do it, probably feels like 15 years ago. If all obtained around the same time frame, it can be convoluted.
Still I remember my books of perhaps when and where only if it is impacted by a time or experience. Those are a few books, I've seen if they're the only slabs that it may be easy to miss.
Dotting I and crossing t is fine, but this isnt a deal gone bad, no need to feel threatened, outed, nor over zealous.
I thought the same when it was mentioned to do pics of safety deposit box, normally of such books, it would seem of course you keep pics already? Since maybe not, you're doing fine accumulating, a sense of enjoying the hobby and medium, so dont bend over backwards