He would most likely lose the case in court. Not knowing it was there was the defense used in most of the baiting cases. Judges have heard it a 1000 times. Unfortunately, most of the time the defendant is probably lying and it will cost your friend.
A good attorney will also give you the practical option. He will tell you that he may beat the case in court, but his fees will be much more than the fine.
Since you readily admit it was all your fault, which by the way makes you a stand up guy who has my respect, call the court clerk and see if it can be paid without a court appearance. If it is and it is reasonable, just pay it for him and save the attorney fees.
If it requires a court appearnace, get your friend to call the D.A. and work something out. In the grand scheme of things for their office this is relatively minor. They should be glad to work it out with a modest fine and let it go at that.
Another option is for him to defend himself. It isn't a big deal and you make a compelling case for some sympathy. It isn't that hard, it's just like traffic court. Don't try to get too fancy. All you need is the truth and your court case. Present it to the judge and see what he says. Unless ya'll are butts he probably won't make the fine more than it normally is even if he finds him guilty.
