Ha. Turns out it was a slight misconfigure as a consequence of this.
The key part was this:
Oct 29 11:28:43 Nethserver httpd: [ERROR] Could not resolve domain bogolinux.net
...
Oct 29 11:29:56 Nethserver cockpit-bridge: Could not resolve domain bogolinux.net
This being a re-herring:
Oct 29 11:28:43 Nethserver httpd: [ERROR] NethServer\Tool\UserProvider: Account provider generic error: SSSD exit code 1
As I still have that message, but everything works correctly.
Cheers.