Best way if you are going for low level egg layers is to knock the whole pack out from a quetzal platform. They will not attack other allosaurus when they are unconscious. Then you can do all the tames at once. For high levels you can knock them all out and just kill the others you don't want.
THE best way to tame anything is to use an argy cage, simply use like 5 dinosaur gateways made of stone and keep one gate door open before you find a dino to tame, once you do, lead it to the cage and then run out through one of the gaps between the gateway frames and obviously close the door and, tadaa, one stuck dino to tame