New answers tagged facebook-groups
I don't now that this is conclusive (eg applies in general) but the top right corner of the first link in the OP has: and the second: so it seems the Create Page or Join Group may be the indication required.
I'm not aware of a built-in tracking feature for that (I'm a group admin too). As an admin of a closed group, the member tools seem limited to accepting, removing and blocking members. Looking at some of the site FAQs, I couldn't find a clear answer to your question, although there are a couple of pages that indirectly relate to member tracking, and both ...
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