Hi @nameyourdomains, as mentioned in the thread linked below, a fix was pushed last month to solve the “connection is refused” issue.
Where are you seeing the terms “publisher username” and “author username”? I assume these map to the twitter:site and twitter:creator meta tags respectively. twitter:site is used to provide the source of the content, while twitter:creator can be used with the summary_large_image, photo, gallery, and product Cards to define the specific author of the content.
For example, the New York Times would always define their twitter:site value as “nytimes,” but the value of twitter:creator might be “aoscott” if the specific article being tweeted is one of A. O. Scott’s film reviews for the New York Times. Check out the meta tags here.