You should be able to add a booking to your profile without linking it through MPO/AM. To do so, log in to the desktop site as usual and go to Manage Booking. On the right side of the screen will be an option to add a booking. You can find the booking by PNR or e-ticket number.

Once added, the screen doesn’t refresh properly but a manual refresh of the page should bring up your booking. If not, try logging out and logging back in again.