User blog comment:BertH/New Forums now available in Labs/@comment-4638257-20121130183053/@comment-1863391-20121201073044

Use this:

display: block !important; }
 * 1) WikiaPage .RelatedForumDiscussion {

Your wiki's admin has chosen to use the  declaration with the property, which typically makes it override other properties as specific or more specific than itself. By using  and slightly greater specificity, your CSS will override the wiki's and you'll be able to see the module again. Hope I helped!