As i understand it a request for files.get only returns my own permissions on a file. How can i read all of them or at lest get a handle for all of the permissions to copy them to another file.
The use case would be an app which creates a related file alongside the original and wants to set the same permissions and sharing settings as the original file on the app created copy.
As you can see from previous questions, currently, this will not be possible for the restrictions you state. Sorry.
Google are aware of the importance of this feature and are working to resolve it as soon as possible.
I faced the same issue and this is the workaround I used.
1) Go to google contacts and add all the members into a custom/new group.
2) Select the file you want to share and instead of searching individuals type group label name and all the members would be automatically added.