Unable to use Acrobat Pro 2020 without sign-in

I have been working on resolving an issue for our customer with Adobe Acrobat Pro 2020 requiring a sign-in to use the software. They do not have Adobe ID's and are using a License Serial Number purchased through the Adobe Buying Program / Adobe Licensing Website.

I requested the client download a fresh copy of the installer directly from their license portal and attempted to package it as a silent install with the offline excpetion granted in the Acrobat Cusomization Wizard. Additionally, I have tried completely disabling all Adobe Online Services or anything related to sign-in services. When I do a test deployment to a virtual machine (with internet connectivity), I can use the software without a single sign-in prompt, through multiple reboots, different Windows users, etc, NO ISSUES. But if I deploy this to a hardware device, as soon as the device connects to the internet, I can't even open Acrobat Pro, it instead goes straight to a sign-in window.

The customer assures me they have never needed to sign-in to Adobe before and according to everything I've read, including Adobes own documentation, considering they downloaded the software directly through ALW as a CLP / TLP customer, they should NOT have to sign in or enter a serial key but all my testing shows that the documentation is WRONG in this regard.

How can I get Adobe Acrobat Pro 2020 working using a silent install package and without needing to sign-in. Or should I be advising my customer to migrate to a competing PDF product?