As for “Publisher/developer information”, I am not sure what you mean. There is not one “corporate IT department” behind the GStreamer code, it is developed openly and the contributors are visible in the git history.
I guess what I am trying to point out is that corporate IT departments can be frustratingly finicky when it comes to verifying software, open-source or otherwise. Even though this information is available in the links that you sent, they want to see it “on the main website” so to speak.
For “developer information”, I’m not entirely sure what that means either, but I imagine that means the list of main contacts (e.g. lead developers).