There's a very easy way to stop division: Have a set of values based in reality, and use that to determine what is not up for debate. The first thing a good troll will do is push at the fabric of what is acceptable and erode the community from there. Some people are inherently unreasonable and therefore shouldn't be listened to. Give them a chance to see the light and if they refuse, give em the yeet.

The reason why neo-nazi communities are so quick to fall apart is because their values are not based on reality, so all you have to do is point out a single contradiction and then watch as they passionately debate themselves into increasingly splintering groups. My favorite that sits on the mantle of shit-stirring pot is "Trump is pro-Israel" which absolutely decimates any far-right community it touches.