very interesting comment - I'd imagine confirmation of that situation requires some very particular information - possibly from the manufacturer of the bottle plus Crown Perfumery themselves. Assume you have already asked Barbara W. Miller for the lady's source of details as to how this unique status has been arrived at ?
I might have missed seeing it, but believed the bottle manufacturer remained unknown - am I wrong on that.
Whilst it's not impossible, it tends to defy common sense that a commercial product such as this - with specially made embossed bottle, crown shaped metal lid, cork and purpose made coloured label - should have been made as a one off.
Despite other examples being unrecorded at the moment, it's always possible one might surface at some time - it's that difficult situation of how do you prove there aren't any others out there, somewhere.
I say all this, with of course, the greatest of respect to Barbara W. Miller, who doubtless has probably forgotten more about this particular area of collecting than I shall ever know.
Forgive the scepticism, and would love to be proven wrong for your sake, but I need to be convinced with something a little more positive.