>I should have been fine according to an on-line DOF calculator.
Keep in mind that the DOF calculator is based upon making an 8x10 print viewed at about 18 inches.
When looking at this image on my monitor (about the size of 8x10) at my normal seated position (about 22 inches), the nose of the stag looks acceptably sharp.
It also is important to remember that DOF is an illusion. There is only a single plane of focus, and as you move away from that plane the detail will get progressively softer. How soft it will appear is dependent upon the captured CoC, amount of enlargement of the capture, and the distance at which it is viewed. So with the deer’s head turned, even if the focus is on the shoulder, the nose is probably around 2 to about 2.5 feet in front of them. With a front DOF of 4 foot that places the nose near the edge of the DOF. So if you look at it with an enlargement greater than the designed calculation, it will look even softer. Add a little back focus to the mix, and the nose will look even softer.