The EMT would TELL him how bad his injuries were, and would have strongly suggested that he go to hospital, and in the event that he refused transport would have made him sign that he had been informed that medica advice was that he get checked out and treated and that he refused. They would do that to prevent them from being sued in the event that he had intracranial bleeding or pressure, or any number of problems that could be caused by a blow to the head, and a broken nose.....there would be a solid written record of findings.
If medical personnel don't do anything else, by jimminey they document, and document and document......they really do...