I wouldn't pay for J unless they confirm J. Once you've paid you have no bargaining power. I'd book in J down, stay waitlisted for J back. Push the ticketing deadline as far as possible (as I recall you are DM, so that should be pretty close to flight time) and then ticket whatever is confirmed for the outbound. Then stay waitlisted for the inbound as a separate booking. If it clears, CX (according to previous reports here will refund the difference between two singles and a round trip). If it doesn't then travel with someone else - Scoot will fly you in economy for about HK$500, Jetstar for $700, Malaysian (via KL obviously) for $900. Stop letting CX screw you around!