LeaverBuster Kick AFK Detection System

So recently, I was playing Shen support with a Jinx ADC. The Jinx was being a jerk from the first seconds of champion select, so I wasn't too surprised this happened. Anyway, the Jinx gave up first blood and blamed me for it even though it wasn't really my fault. What happened was she ran at 2 full health enemies at half-health while I was just walking down lane, she died, blames me for not being there.

Her message looked somewhat like this: wtf shen what r u doing standing all the way back there u dumb***.(She was using this sort of language/attitude from champion select.) I responded with, "If you wanna cry like a 5 yr old, I can mute u right now." (I admit this is a bit harsh, but I was getting sick of her attitude at that point - I hate when players blame everything on their teammates, especially with that kind of language.) That was enough for her to DC. Literally 1.5 seconds after my message, she DC.

About 7-8 minutes later though, she reconnected. We asked her what she was doing, and she replied saying she was just staying in spawn to earn her money (IP). And then she just sits there in the fountain insulting us for 40 minutes, and clicking/moving around the spawn every 3 minutes or so to avoid the AFK kick. So that's the problem.

Riot/LeaverBuster, there's got to be a way to detect players who are not participating in the battle and are just fountain sitting. I mean if someone is going to rage quit, please do not let them add insult to injury by insulting the team in the chat. It also makes reporting the player harder (for that game it was easy - Offensive Language and I added in the description what I said above) however, if a player doesn't do anything else punishable during the game and is just walking in circles in the fountain, reporting for AFK will not work since AFK reports don't go to the Tribunal. Instead they go to LeaverBuster, and that system is automated, so it can't detect a player "fountain sitting". RIght now, I have been using Assisting Enemy Team and adding a description about it when this happens and the player didn't do anything else punishable, however, I have a feeling I'm not doing this right.

TL;DR/summary version: Riot needs to find a way to detect "fountain sitters" who are just clicking to avoid being kicked for AFK.