It’s well known Flurl had three types of videos; such as native video links, Youtube mirrors and other sites. As seen on the picture, it’s mirrored from Youtube.
3)It used to be a public video. In watch?v=CDNGQIBLaKc&feature=related, it clarifies that video has been featured on “related videos” part of the youtube; which means it’s not a private video at all.
Now, with the informations we got; we could focus on this lead. Things we could are: