Is any system really foolproof again the human will to fuck your game ? Nope, never. If some guy is ready to risk a ban just to troll you, he can always find a way.
Just don't care for lol more than it deserves, remember it's still a game and an anonymous kid trying to taunt you behind a computer.
Look at it, go "OK, you managed to ruin loose 20 min of gaming for me, at the cost of your own 20 min of gaming. Good for you." Play the game anyway seing what moves you can make in the 20 min you have to kill. Alt-tab and read website while moving once in a while if you're sure your teamates are on board. Or just Alt-f4 and launch another game if you're getting bored of this shit.