If he does decide to mount it, he still can even though he cut the head off too short. You can always use the skin from another deer.
My father had gotten a big buck a few years back, but it had the mange or something and it's pelt was horrible. He used the pelt from another buck he had gotten as well and combined the two into one, plus the nice pelt (small horns) had a total white throatlatch that went all the way down the chest, which is highly rare, so he combined them and got the best of both worlds in one mount.
A skull mount is nice too, plus alot cheaper. The price of mounting is expensive. I showed my husband the pic and he is extremely envious!