This plugin was designed specifically to deal with idiots like that. Unfortunately, the plugin is not supported and is way out of date.
This thread is to help people with this plugin and not for server advice, however, since I'm bothering to reply, I might as well give you some advice.
I've been running servers for 10 years. If it were my servers and those guys are team-stacking to the point that people are so frustrated they quit, then the team-stackers would get warned, kicked then banned if they don't stop immediately. The reputation of your server is not worth a thing if a handful of people are ruining it and soon no one will play there. Tell them to stop, if they don't get rid of them. They aren't worth the trouble and they will easily be replaced by new players if you have a decent server.
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