This problem doesnt sound related. Re-read the OP so ignore this comment.
What you are describing here is more of a processing error on the printer when it comes to publishing the PDF document to that location. The printer is able to access the destination, you have confirmed that so I dont think security is the problem. Either something on the printer is corrupted and needs to be reflashed via a firmware update or soemthing is tampering with the connection the printer has to the destination, dropping packets or routing incorrectly so that the entire contents of the job do not arrive as they should.
Your firmware date code appears to be a little out of date. I would try updating the firmware and see if you can repair the damage on your own. If not then the printer may need to have its formatter replaced and at that point it may be easier just to have the entire thing swapped out for another.
If you have access to network sniffers you could try to capture the packets between the printer and the destination to see if you can observe any odd behavior. Perhaps communication to this destination is going through some strange node in your network that is causing issues. Something like WireShark would could be helpful.