Several years ago, I shot a nice 10 pointer right at dark. I shot, the buck took off but stopped, then walked off as if nothing was wrong. So I sat there quiet until it was completely dark. I got down and carefully made my way to the point of impact. I looked & looked and nothing,,,no blood,,,no arrow,,,no sign but the disturbed leaves where the buck launched at the time of the shot. So, not wanting to risk it, I backed out quietly. I made my way home reliving the shot over & over again as we all do in such cases. When I got home and started taking off my hunting clothes I noticed that my boots and lower pant legs was literally covered in blood!! I couldn't believe it because when i was in the darkness of the woods with only a headlamp, I did not see a single sign of blood. It left me puzzled to say the very least. I went back out in the dark with my headlamp to look at my hunting clothes and again, I could not see a thing!! Found out that with certain grades of LED lights turns me color blind. I recovered my buck that night but what a way to find out.
Another time I hit a doe in heavy snow,,,the blood balled up in the snow and froze covering the redness of the blood. I seen the doe go down but most of the blood was covered in snow.
These are my two experiences in such a thing,,not saying who's right or wrong,,just sharing my own experience here.