"Theme: Grey" Not sticking when opening new, separate PDFs

I work for an IT frim helping a very particular client with maintaining system wide dark mode for all of her programs and experiences. Again, very particular, to speak in the appropriate terms.

She is an Acrobat Pro user and is constantly enabling the "grey theme" feature when using Adobe. However, when she closes Reader to open a new document, the theme does not stick or remain grey. It goes back to white. Now, myself and my colleauges are aware she could simply open a new document to edit from within Adobe simply by using Ctrl+O or by clicking on a recently opened document from the home screen to keep Adobe (effectively) open and not closed. Unfortunately, she is not keen on doing things that way and is very stubborn in changing her workflow so "dramatically" as she puts it.

I have tried all of the guides here on the Support Community and there is no solution. Is ther another way? Maybe changing a registry key or something to permanently set her Adobe to open in a darker color setting? Another thing I had noticed is there her Adobe is not signing her into the program immediately (or at least not reflecting the signed in nature) and that is causing her to worry more. Creative Cloud is running in the background and is set to start when her computer starts. These "issues" began when she was having an issue with her E-Sign not working because file sync was turned off in the Admin settings. We have since changed that, which presented us another issue prompting a call into support for Adobe, as file sync was not working for her still. Regardless, we have uninstalled and reinstalled and now everything is broken.