I think this is the same problem that I am having. The file is uploaded, but it is not given view permissions. The permissions are set right on the folder, but the uploaded file is not inheriting them. The code used to work, but suddenly stopped.
When I upload a file using FTP, the file has the correct permissions and can be seen on the site. When it is uploaded using DFP, it cannot be seen on the site.
Any thoughts?