Sorry, that's not Riot's problem. They will only overturn bans if you can convince them that they made a mistake.
In your case, you've admitted you have no idea whether or not you did have scripts and/or 3rd party programs installed due to your own actions by copying from a friend. Secondly, there is no way for Riot to know whether you copied your friend's files due to some files getting corrupted, or because you wanted some of the hacks he was using.
You made a very poor decision (probably in all innocence), and are going to have to suffer the consequences due to the fact there are so many cheater and liars around.
By all means, send in a support ticket. Make sure to reply to the first canned response you get to get a personal answer. But, in my opinion, your chances of getting your account back are minuscule.