Get it to where it is running away then drag it a dead body so it will eat it then start healing and then knock it out while it has the healing symbol over its head if you do it right then it's good will rapidly drain
An argentavis can't fit through a ceiling with one tile missing, but a pteranadon or lymantria can. Build a trap with one corner ceiling missing, aggro the argentavis, fly in one side and out the missing ceiling tile, and land. Dismount, run around, and close the entry door. Tame safely at your leisure.