I think it's a great theory, but I believe Zoro will die, but only for a while. Devil fruits can awaken right? Brook has a devil fruit that gives a second life, so what is his awakened power? Most likely he can bring back the dead as long as they have not been dead long (most likely or that would just be OP). Zoro will die, meet his inner demon, Brook brings him back and hes stronger than before. Now I'm not going to do a theory in this comment but its just a little opinion that I would be happy to do a theory on... Most likely would just be about SH awakenings in general though.