Did you copy the url from the address bar? I noticed that sometimes videos wouldn't upload if I copied and pasted the link from the address bar, so I started using the "share" button instead, and that usually fixed my problem.
I'm sorry the site has been giving you so much trouble, and that I can't think of any solutions. I always liked the website, but the various glitches can be so frustrating. I wish there was still someone to contact about these kinds of things.
As a last resort, I would be happy to post the video for you if you're ok with that (though unfortunately you won't get the Jpops). Hopefully the problem will fix itself somehow though. Best of luck!