There is no generic recipient-independent resubscribe link in this flow

For school administrators using GiveCampus Outreach. Controls can differ between the classic email editor and the newer Composer editor.

The resubscribe URL contains a signed token for a particular unsubscribe record and topic. Use Send Resubscribe Link for the appropriate recipient/record rather than copying one person's link to everyone. Sending the request does not itself re-enable mail.