Knocking it out: First, you will need an argey, 2 crossbows, parachutes, tranqs, and grappling hooks. Fly up to the quetz with the argey, hop off with parachute, make sure argey is following you,grapple to it then whistle attack target on the quetz, then when you get close enough to shoot it with a tranq arrow, whistle passive then shoot, quickly whistle attack target on the quetz because it will flee far and fast. Repeat this until it is successfully knocked out.
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.