Self pwn on my end. Issue resides in that I use PFsense with Haproxy to then get to the NS guacamole install. NS Fail2ban sees my IP address and works like it is supposed to if I were connecting to it directly but it does not block connections that are sent through PfSense’s Haproxy. I am going to confirm again this is reproducible behavior with Nextcloud also being proxied in the same way on system.
Exerntal IP< =>Pfsense <=>NS Guacamole.