I went to the #ejabberd chat channel and got pointed to https://git.chinwag.org/chinwag/ejabberd-auth-mastodon
This solved all my issues in one go. 🙂
My mastodon user/pass are also the same user/pass for the jabber server! ❤️
Licaon_Kter or Licaon Kter, if you ever read this; thank you!
This is a private instance for members of the Ligthert family.