Nextcloud WebDAV sync not working in iOS, works in Windows

Has anyone perhaps had luck syncing Joplin on iOS 14 to nextcloud by storing the contents of the Joplin app into a folder that the nextcloud app is already syncing (Basically syncing through a networked directory/file system)? I'm not sure if it's even possible on iOS14, but I might try to create a folder for my mobile notes to be stored, then tell nextcloud to sync that folder to the server, then directing my desktop joplin app (which is working fine) to sync to that same folder via webdav. Has anyone tried this who can spare me a half day of toil?

Edit: after looking through this thread it looks like the idea for syncing through the file system has already been entertained with no luck.