The only thing you get is lounge access. At no point is your MPC status linked to your booking/ticket. Upon arriving at the lounge, explain that you are on a staff ticket and you're a DM. They will take down your Cathay membership number and check it on the computer to ensure that the name on the boarding pass matches your account and that you're entitled to access the lounge.

Your status will not be recognised anywhere else under any circumstances.