Disorderly Conduct: Disorderly Conduct Charge for Actions While Tailgating

What are possible outcomes of a disorderly conduct citation charge, first time offender? Do citations help the defense in court? - mores specific questions at the bottom of my post.

Backstory:
I was in Tennessee for my brothers graduation recently and my family and I attended an event that is quite popular in the area. I attended with my family in a tamer tailgating area, while my brother was tailgating out in the "college area." I ended up leaving with the rest of my family late in the afternoon while my brother stayed behind. About an hour after leaving, I got a text from him saying that he was just given a citation for disorderly conduct. Because he said he was only given a citation and not taken to jail so I thought nothing of it. Well he literally just told me the details of the incident and it seems it's much more serious than I originally thought.

Apparently my brother threw an "object" into the air which harmlessly landed near (according to him 15 yards, but lets say it was closer to 5) a few people standing (the object did not break as the entire area was grass). By this time the events at the track were over and most people had left, but a few police officers saw what he did and approached him. They then handcuffed him and took him to a mobile booking station where they finger printed him and took a mug shot. They were originally going to charge him with public intoxication and disorderly conduct, but according to my brother, he was polite and responsive to all of their commands so they dropped the PI. Once he was processed my brother was given a citation stating that he acknowledges the charge and has to appear in court, but could leave on his on recognizance. Now that I've heard the full story I'm starting to worry. He just moved back home (1,000 miles away) and is applying for jobs. I have since researched disorderly conduct penalties in Tennessee and found him a decent looking law firm to call in the morning to consult with.

Questions:
My question is, will the fact he was given a written citation instead of actually going to jail and being arraigned benefit him in court? Additionally what are some of the penalties for a disorderly conduct charge? I should add that my brother has a clean record and this is his first offense for anything greater than a speeding ticket.

Also what are the chances that the charge will be on his record permanently? My hope is that he'll be able to plead guilty to a lesser charge and avoid having a criminal conviction, but I don't know how the charge is normally handled.

I guess I'm just worried that one act of stupidity while drinking will negatively impact his job prospects possibly for the rest of his life. Especially considering that he did not throw the object with negative intentions, it was in a "celebratory manner." Anyway if anyone has dealt with similar charges or knows anyone who has, please let me know what to expect. Thanks!