I'm speculating that the calf had been wounded and later died unrecovered, otherwise the arrow or at least the arrow point would have been recovered.
I'm also thinking that the shot placement may not have been as far off target as some may think. It stands to reason that the hunter may have been aiming for the paunch or soft area of the animal so as not to have penetration of the arrow stopped by ribs and shoulder bones in a frontal hit. But he missed target slightly hitting the hip bone. A paunch hit would have been lethal and caused the animal to drop out of the herd to die within sight in the open terrain.
