Originally Posted by
Flying Machine
As an aside, if I credit to COPA can I show my mileage plus card to gain access to the lounge in the future.
Yes you can, and it is fully permitted as per the rules. However, I did write before "to avoid confusion". Hopefully you will gain access to all lounges without issue (and also get an extra bag as you are entitled to, if needed), but you might have to deal with a couple of agents before someone who fully knows the rules will grant everything