Even if they are older replays, they still aren't good enough to get you in, i'm afraid. Sure, you may be better than that, but we can't just read your skills out of thin air, y'know?
Also, no, multiplayer replays not allowed. BUT, your replays doesn't have to be an individual split or decap, it just has to include (a really sweet) one. So don't worry about hitting Uke before the split/decap, as long as it's there. Unless Splinter says otherwise, of course.