The upload date for the original upload (https://youtube.com/watch?v=dVzr_e0ab84) is based on a personal download I have of the original upload, where the metadata lists "2011-04-30 08:10:38 UTC" as the video's encoded and tagged date. The URL comes from both the Niconico reupload of the video (https://nicovideo.jp/watch/sm14322390) as well as an archived page of "Fully Powered-up Octagon" (https://web.archive.org/web/20120816173622/https://www.youtube.com/watch?v=Q0Uo7F1UYZ4) that shows that the upload was from Catman0003 (Tosochika's early alias).
In addition, this video seemed to have been part of a Diddy Kong Racing centric contest, where it was deemed as the best of bunch as shown in the following video by AtomicBaby123: https://www.youtube.com/watch?v=RZH3x98NLe4
An archived page for "Jack Black Stole the Precious Octagon" (https://web.archive.org/web/20130216183718/http://www.youtube.com/watch?v=wT1SAe3nnys) links to Tosochika's video "Octagon Racing" (http://www.youtube.com/watch?v=jyFjHF7C3TE) that is likely this video's original YouTube upload. However, the original upload page itself hasn't been archived, at least on the Wayback Machine.
The bulk of videos uploaded between 2008/06/17-18 on あるけみ are reuploads from the creator's previous channel シュウ. Most of these original uploads have been archived here: https://www.nicolog.jp/user/969721
These channels have been bundled together due to them being included under mylist/7458065, which labels the videos as creations of a single creator. Furthermore, a lot of the videos spread on these different channels link to this mylist as well. This mylist is saved under the account named "BBQ", thus I've added that as the predominant username for this creator for now.
Acknowledged by Terry Crews here:
https://twitter.com/terrycrews/status/317821801122131968
https://www.facebook.com/realterrycrews/posts/142127789292658/
The original two uploads of this video were not exact copies. The YouTube version (Wy_FxkOMPeY) was a bait-and-switch version that switched from Blue Archive to Inmu, while the original Niconico version (sm44094810) only features Blue Archive. After the YouTube version was deleted, this bait-and-switch version was reuploaded on Niconico (sm45424506) though under a different account.
The original upload's metadata as presented here is based on the following archived page. The upload date is an approximation based on the work being uploaded "5 days ago" on the snapshot's date of 2009/09/07. https://web.archive.org/web/20090907115542/http://www.youtube.com/user/MatrixMarioX