nope it will be a long time before anyone discovers an exploit espescially without a jtag jst like it took a long time to find waw zombie mods co-op :mellow:
If I heard correctly you can not because you need Xbox Live/specific update (maybe a title update?). To play the map Call Of the Dead and the only way to use a GPD now is if you go offline and delete the title updates (unless they fixed it).
Hope that answers your question. Have a good day and best of luck on finding an alternative solution if I do turn out to be wrong.