There is usually at least one quetz roaming around the red obelisk and craggs Island. Go over there and kill any and all quetzals that aren't of your liking, and then fly to above the nearby swamp or The end of the red lake (or further). Then fly back and be sure to check above the beach area between craggs and the obelisk which is separated to craggs by a thin water path. If no quetzal has spawned there then look around and west of the obelisk. If no quetzal has been found in either area then try flying further away or waiting 10 sec before going back. This method works especially well on evolution event which is when I've mostly tried it. Good luck!
I Was on a Tapejara and somehow knocked one when I was on lvl57 and that fool quetzal fell and landed in front of a group of allosaurs. That was the first and last quetzal I found in my game😭.... Now search continues but no luck..... #RIPMe