TL;DR: Fix the DNS settings
We resolved the issue. After carefully reviewing the log files, we identified that there was a DNS error causing the authentication as well as other functions that need the web to not work. The solution was to go to the dashboard of each node and correctly set the DNS server IPs.
The reason it was bad to begin with was because we migrated from another building and the router DHCP was pointing to a local DNS server that no longer existed. So proxmox auto configured this from the router.