For the question on this post. Flagrant misconduct includes but is not limited to striking, butting, elbowing, or kicking an opponent. In reality the difference between Flagrant Misconduct and unsportsmanlike conduct is a judgment call. I have not seen any of the above mentioned violations in my short career as an official, but I have usually seen these infractions called by other officials as unsportsmanlike conduct. It really comes down to what he believes was the intent and severity of the situation.
Wrestling is a tough sport and emotions do run high.
The point is that the penalty should fit the crime. Now as to the specific situation described in the original post. I probably would have called it as Flagrant Misconduct. Someone was injured and the circumstances surrounding the injury would make me believe that it was intentional. However, if the match official was watching the pin, then he may not have seen what happened.