Hi @Richard_Medina,
I ran this by one of our developers who had this to say:
yes, we only check against users assigned as participants to the submission it probably does make sense to check against the author records. but this could only be done for matching email addresses. author records are not associated with user accounts.
So, that said, it might make sense if you wanted to file this as a feature request. You can do that by creating a new post here on the forum and selecting “Feature Request” and following the template describing the issue on the new post following the template provided. You can use this post as a reference as well: Automatic certificate for reviewers and authors
-Roger
PKP Team