You just need 2 Friends with a ptero each; mate1 have to grab you, mate2 have to Fly under it and then bug the quetz circa at his Chest zone. Shoot w/ Longneck, put some Narcos in and that's it. Quetz Done!
The fun way is to jump off and grapple to your argie and whistle it to attack and since argies are slow it won’t catch up in time so tranq till it goes out also bring parachutes and consider liking so more people will know
If you drop a quetzal due to knockout, and it lands next to a giga...just know, the quetzal belong to the giga. Now you get to watch your would be quetzal get eaten by a giga. Now you can go home and cry.