Most of the books were uploaded legally, but there was trouble taking them down or they popped back up after being taken down (which actually does happen on Amazon even when the publisher is not screwing up). Whether it is 'true' or not it is Dorchester's claim and they will chew up billable hours pursuing it. So unless the author is independently wealthy I can understand not trying to solve the problem by throwing lawyers at it.
Some states have great probono legal defense for authors though. If any of the authors are in Georgia, there is a group there that can help. As of when I used the service 'artist' included the creator of any work, including fiction and other artistic mediums.
http://www.glarts.org/GLA/artist.html
They went after Random House (Italy) for me when they illegally published one of my stories which they did not acquire the right to publish. The publisher instantly paid me for the stolen work, and it cost me not a dime.
Other states have similar programs. Authors should check in their area for such assistance. Not all states have them, but those that do are typically very creator friendly and want to help you protect your work.