The only people who can lock the topic is the person who created a topic or in extreme cases the forum administrator(possibly the mods but i'm not sure). So my guess is buff88 locked the topic hoping this accusation will just disappear, but in reality has just made it worse on himself and the site.
Totally bad for them, they've fan the flames to get more bigger with that deed because they are implying that they're guilty and that they don't have any plans to resolve the issue they have against OP.