I deleted the last notes since the proposed solution was broken.

The following should work a little better; it is a script that retrieves the contact list containing a target pubkey and then verifies that this pubkey is not already in previous contact lists for each user; this should prove that it is a person who started following the pubkey for the first time.

nostr:naddr1qvzqqqr4gupzq77777lz9hvwt86xqrsyf2jn588ewk5aclf8mavr80rhmduy5kq9qq8xcctnwskkvmmvd3hhwetjwvwqremz