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Of course there is a chance that something had been at the Library of Alexandria at some point of time before it was destroyed (several times, actually).
But how would we know? Unless we find something written alongside the document in question that states said document had been at the Library before.
Which is hugely unlikely. Even today's libraries don't keep records right alongside the books, and I don't think at that point of time anyone kept record where a document had been.
So, do such legacies exist? Possible, even likely. Do we know about it? No, not to my knowledge.