Hey Failed,
I'm really sorry you've got to deal with these kinds of experiences, I have seen it too and at best it's not an enjoyable experience. This is kind of a pitfall of how Riot approaches banning bots, kind of a necessary evil to help prevent things from getting worse: Bots are banned in waves periodically (maybe every 2 weeks? there's no public info on that) rather than immediately upon detection. While this is really frustrating to players in your position (particularly newbies), it is done so that the botters have a difficult or impossible time figuring out how Riot is catching them, because they would use that information to adjust their programs and evade detection and consequently ruin many many more games and profit immensely while dealing great damage to the game beyond a few days or a couple weeks at low levels.
I think they could make some improvements right there, such as auto banning if they exceed a certain number of games after detection rather than waiting on the ban wave (given too many games, they still couldn't figure out how they got caught). Riot is absolutely banning these people, and they are quite easily caught, there's just a gap where they are a problem before they get the boot. I know it's a painful experience for you, but please hang in there and try to understand why things are like this!
I also understand the urge to flame bots or players that are just trolling, but it really doesn't help the situation and makes the game a little (or a lot) worse for the other legitimate players in the game dealing with it just the same as you are. Bots and troll absolutely don't care if you shit talk them, and with trolls they are probably looking for negative reactions like that; ignoring, muting, and reporting them doesn't fix any damage they did, but it does help improve the match at hand for you and reporting helps get them removed from the community so others don't have to deal with the same thing.
P.S. The bot has already stopped playing, the only reason this would happen is if it already got banned, so I'm not going to submit another ticket since it won't help, but I do think I'd like to make a post proposing the change to the ban wave.