I don't know what I'd do. At first I want to say I'd leave it as is. However I have had a fish touched up when one of its fins was messed up. Basically the same thing.

There was also a buck that I spined, and in the melee to quickly get another shot into it, I shot one side of his rack off. It was a smallish buck and i repaired the rack myself with some wood putty and stain. But I had caused that blunder, the deer was intact with the 1st arrow.