I also use a Windows PC and Android tablets. The Companion is only for connecting to another device, to load from the same device use the 'local file' choice. I have 2 local files, 'for tablet' and 'on tablet' on my 2-in-1. I use the 'for tablet' when I need the 'local file'. Hope that makes sense.
Dell Latitude 13.5" 2-in-1 Ubuntu/Win 11
Samsung Note Pro SM-P900 12.2 Android 5.0.2
Samsung S7+, Android 12
Samsung Note Pro SM-P900 12.2 Android 5.0.2
Samsung S7+, Android 12