The linked log is definitely an important part of their interactions, but I also feel fairly certain I'm missing big chunks of their relationship. I could wait and see if the other person involved in that log is going to offer any links, and if Zevran's player will have links for the current situation with Cade, but right now I'm kind of lost.

Do you have logs for any of their other interactions that might help give context? Or was it all handwaved? Even logs that don't include Cade, but you think are important, I'd be happy to incorporate them if I can.