Why are my Windows Servers ignoring group policy for Automatic Updates?

I have a number of Windows Servers running both Server 2016 and Server 2019 operating system, and they are ignoring both local and group policies that disable automatic updates. I want to manage updates manually via a 3rd party software called Automox. I have been using it successfully with Automatic Updates disabled until recently, but I noticed that some machines have started rebooting randomly to apply updates out of series with my maintenance Windows.

I have used the sconfig utility to set Windows Updates to manual. I have also applied group policies that disable automatic updates, and the corresponding registry keys show up as expected, but Windows Update apparently has decided to ignore these settings. Instead of "Some settings are managed by your Organization" showing up in the Windows Update control panel, it just reflects that Automatic Updates will be installed over unmetered connections.

I have disabled the Windows Update Service on Production Machines for the time being in order to prevent this from recurring on business critical machines, but I need to get the policy issue resolved ASAP.