RE: You make the call??
To shorten my response to this hypothesis, I am going to pretend I do not know this buck and his territory, and where he will most likely try to get.
Could be a liver hit, but seems more to be a hit that was high, pierced or clipped a lung, and slammed into its should or leg bone. If you cut the large aorta that is at the top of its heart, which is in the path of a high hit at that angle, he is down for good and will die in matter of minutes, if not seconds.
If the shot only hit the top area of the lung(s), within minutes, he will be up and on his way. He instinctively knows something is wrong. It is getting dark (predators) and he knows bad weather is imminent. His brain is now in full survival mode. Primitive instinct will take over and he will head for dense cover no matter how much he is hurting.
I am going to (eventually) try to get into a downwind position and as close as is possible without spooking him. I may not be able to see him, but hopefully I can hear him and get an idea of his direction of travel when/if he gets up and moves on. If I hear him move on, I am going to quietly go to where he was hit and where he was laying to look for blood and determine what the blood tells me about the wound.
If I am out of coffee and food, and I do not have my cell-phone on me, it appears I am going to have a long, hungry, and wet night. However, if I am alone, I know that if I have not returned to home or camp within a certain period, there will be someone on the way and I will meet them at my truck or on the 2-way. He or they will have coffee and some food. And then WE will have a long night, if the buck got up and moved on.
If I do not stay, the ' yotes will have had a feast before high dawn hits. [:@]