I had an AmEx account that they turned over to a CA at about 90 days. The CA called me once and was very aggressive. I asked for their address so that I could send a CD, and after repeated requests for their address, the guy finally gave me their fax number. I never did fax the CD because I decided to wait until I got something in the mail from them. Lo and behold, the next contact that I had was from AmEx telling me that they had pulled the account back from the CA. They asked me if I had sent a CD to the CA and implied that the reason they pulled the account back was because of the CD (that I only threatened to send).
So it's possible that if you CD the CA, they may send the account back to the OC. But, as Nascar said, it could also cause a risk of lawsuit, especially since it has already been charged off.