Solution
It seems that file permissions are altered when a folder is renamed through WebDAV, the file permissions are altered in Linux, which limits the user groups ability to Read/Write to the text file. A example of this is shown below.
A workaround is to rename the folder by accessing the controller via SSH, and using the
mv command in Linux. This allows you to rename files and folders without altering the default file permissions, or custom permissions set by the user. An example of this is shown below.