LOLyou could try contacting the original uploader, requesting he re-up the video file(s). however, if it was me, i would ignore the request because you are not a significant contributor and there is plenty of other free stuff here for you to leech.
I always ask people if they want a refund. "when they say refund?? i didnt pay anything?!?" I just laugh and reply, "oh i guess you will work it out"