(Background, for those without museum experience: The duplicate is a specimen made from the same plant or the same population and usually shared with somebody else.)
I consider using ID’s from iNaturalist to ID a specimen to be similar to having somebody identify a duplicate. When I annotate my specimen with the other person’s ID, I write, “duplicate determinated by AAAA BBBB 2023.” I would use an iNaturalist ID on a label, and I would write something like, “iNaturalist observation #11111111 determined by AAAA BBBB 2023.” Some note like this makes the process clear enough that a user of my specimen can evaluate how reliable to consider this identification.