This article explains what is the zTruncatedFolder.
In OneDrive, folder and file URL are limited to 260 characters.
In Google Drive, the length is unlimited.
In order to migrate Google Drive files and folders whose length is above 260 characters, Cloudiway platform truncates the urls to fit within the OneDrive limitations and migrate them to a folder names zTruncated at the root of the OneDrive.
Inside this folder, a file is created that contains the original location.