When I'm using Office, the files come from a shared directory accessible as Z:

I use scripts to automate everything - including allowing wine to use Xwayland (because until I start the application I want, its userid is not allowed to show content on my display)

If you want to try using wine with different user ids, try to start with a directory in /tmp like /tmp/wine which is group writable, with your windows app and your user belonging to the same group.