As a follow up to this post (Sorry for the delay, just finished a project that required 14 hour days for the last month.) - I did finally get this working.
My router settings were fine. On the server I went back and reran the firewalld command to add the https zone and reloaded the firewall. Then the certbot command ran fine and issued my certificate. So likely my user error but just something to be added to the check list.
Thank you all for your help. It was your comments that helped get me on the right track.