Did any of these solutions work for you? I have a similar use case. I need to set some variable recipients through "Event parm 1 contains recipient," which will be sent as "to." However, I also have additional variable emails that I want to set as "bcc." This was being handled using email.addAddress("bcc", gr.getValue('X')); in the email script. But there's a defect: when "Event parm 1 contains recipient" is empty, the email is also not sent to the BCC recipients which is not empty.