Where a writeback extension is used, users are capturing data in a app and the data is then added / updated in qvd files in a space.
To allow for the writeback, users need to be given edit rights in the space.
However, you do not want the users to be able to see or open the .qvd files in that space as this will allow them to see data captured by other users (if there are security considerations)
Please add a option where members in a space can edit data files in the space but but not be able to see or open those data sources.