There is a WebDAV app. It’s just Apache http with the webdav module enabled. You can use it to serve up static html. In addition, you get the WebDAV functionality. I used it for Document authoring and sharing on the Internet, using authentication and TLS of course. WebDAV actually works quite well across a WAN. I could mount WebDAV volumes on my laptop or phone while out and about and had complete access to all my documents.
Did you configure storage for the WebDAV app? You have to configure the Hostpath to a dataset on your NAS where your content is kept. The dataset is then made available in the Container at /shares.
Anyway, it seems you’ve found the solution that’s best for you.