I am testing a glitch for die rise to get you the highest rank in zombies, sadly you need dir rise for this and an elite account (I have season pass but not sure if you need one). What I do is log on your account (kind of like recovery) and ill tell you what to do on elite.
I will be releasing a tutorial along with my leaderboard glitch tomorrow.
Please vouch when I'm done if it works for you. (It worked for me)