grow your wiki
Key individuals for a particular project start complaining about being "kept in the dark" and that nobody is reporting on the work done for the project. The information is actually all available in the wiki but the plaintiff keeps ignoring it or referring to other out-of-date sources.
Typically, an individual keeps ignoring the wiki until they are so out-of-date with their project that they issue an email to all parties involved requiring a teleconference or a meeting to recap or make a status for the project. Anyone in the team can then issue a "Reply to all" message with an hyperlink pointing to the wiki, explaining that all info is... "just a click away."
This reaction is also referred to as the DefendYourself pattern.
Note that the fact that all parties are CC is important. This gives political weight to the reply while keeping the conversation at a polite tone. Still, caution is advised in the wording of the reply as to firmly state your point without offending anyone.