The extreme circumstances that would lead to litigation would also lead to, before it ever came to that, appropriate action against posts in the shed.
The rules of the shed are no threats, no libel, no bigotry, so people know to expect that they will be free from those three things. Nobody is going to sue Huskerboard if those three things aren't happening. If those things ARE happening, then the board could get sued, but only if the staff was negligent in weeding out the problem and enforcing the rules, which they have been doing, and which you are pissed about.
tbh no one's going to probably sue over those things because there's not going to be enough damages to make it worthwhile for any lawyer to take the case.