Definition: "measures taken to offset or minimize damage to reputation, credibility, or public image caused by a controversial act, remark, or revelation"

This is an innocent act (going to a game as a work group) that could be perceived as controversial by pure coincidence.  No damage was done and there is no reason to believe that they were trying to offend anyone.  The university putting out a statement about dressing as missionaries is damage control, this is just clarification.