The uploader has not claimed they are an author; it doesn't say "Creator/Co-Creator" on that page but rather "Re-Distributor". They don't know the original author and have put 'unknown' in the list. If you do know who the original author is by all means let me know.
You can access submissions through your sublog or via the event notification you received when it was withheld.
As for your last message no credit theft took place. Both are re-distributions (ie, uploader is not the author).
anyway they have no author and if he was the creator he will put his name in the credits, hes not a credit thief then if i could flag i will flag improper credits.