Did you ever find what variables trigger the meeting with the exchange? I fought the Red Eclipse, but I am not getting invited to meet with the exchange. Correct me if I`m wrong, but shouldn't I get invited after fighting the Red Ecllipse?
I was playing around with the saved game editor, and I figured out how to trigger the invitation to meet with the exchange. Under Global Variables -> Numerics, change the the value of the variable 300NAR_Exchange_Gap to 8. Ive noticed other people are having this problem , so maybe this information will help.