I managed to book copa with huge caveats. Married segment availability only (lim-pty-gru), tons of un bookable itineraries (tested by clicking book, if I can get to the screen to input passenger names, it works, otherwise it gives me the error message that itinerary is no longer available)
Economy only worked, business kept getting the error above
Certain routes that show up on United but not Aeroplan unable to be booked