I saw your post and thought it was quite funny.
I have noticed that the admin "acts in mysterious ways" on this site - at least as it relates to me. I've just chalked it up to the fact that 2/3 of the site here hate my politics and the admin falls into that camp so he never bothers responding to anything I send to him using the Help -> Customer Service Request Form.
You on the other hand are a completely non-controversial person here, and I would have expected you would have received at least a short explanation as to why he removed it. The video was completely innocuous. Meanwhile, a "hidden / deleted member" continues to post videos/gifs of elephants shitting and writing "Fuck Off" in huge text sizes directed to other members and that seems to be A-OK. Maybe that guy gets a pass because he appears to be mentally unstable, and a more stringent set of rules apply to you because you appear to be quite sane?
Bottom line: If you dare, repost the video and see what happens. It might get the admin to at least send you a note as to why he doesn't want it here.