I am a lawyer in CT.  I suggest that you obtain a lawyer to help here.  You want to go into the case with witnesses and people that can testify as to what happened and motivated this incident.  Also the statute of limitations has not expired.  Have your fiance press assault charges against the guy. This will put pressure on the state to make some kind of deal where the guys can say this was an isolated incident and see about getting the charges nollied.