Perma ban appeal for a friend who was accused of hacking, but was not.

Dear, Riot League Boards Recently had a friend of mine get permanently banned on league of legends and this is her first time. She was reported for having third party software,but did not. I have no memory of her ever getting banned in the past nor memory of her every having thoughts of using third party software. I know i'm going off of memory and no hard facts here, but if having a clean record until now is good enough I'm sure there is something they can do right?

     I'd like to know if there is anyway to get her ban lifted because this is an unjustified ban. I'm not sure if this helps, but the person also has a PBE account which means that the account was clean, until now. If there is anything more that I need to prove/ lift a ban from an innocent summoner than please tell me.

Thank you.