Gee, I don't know. There are a buttload of CAs out there. Some of them are bound to know each other. It's just a question of whether they're trying to run a business or waste their time finding out who is disputing their friends' entries. I don't think so. I'm not even sure why it would matter. Why do you think it would matter, or rather, what is your concern with the situation?
They would probably have to pull your credit reports, and contact other CAs on them. If the account is paid, there is no longer any permissible purpose to pull. Pulling reports to notify other creditors is not a permissible purpose. A CA with an outstanding debt would have PP, and they could contact other CAs on your report, such as ones indicating "could not locate". (There have been cases of CAs pulling reports just to look for accounts they could collect on. That was slapped down years ago, by both FTC and private suits, as not permissible under FCRA.)
