You could give up trying to change their policies and do an ugly hack: find a tool that will let you programmatically insert metadata into the new format, then

You could give up trying to change their policies and do an ugly hack: find a tool that will let you programmatically insert metadata into the new format, then kludge up something to go through your account, screen-scraping the metadata, grabbing the video, and calling the metadata-insertion tool. Or since it sounds like you maybe have all the videos already just screen-scrape the metadata, figure out the appropriate file name, and inject the data.