I decided to dive into ModerationCenter.template.php (see you my beloved brain! ).
First question:
<strong>', !empty($report['board_name']) ? '<a href="' . $scripturl . '?board=' . $report['board'] . '.0">' . $report['board_name'] . '</a>' : '??', ' / <a href="', $report['topic_href'], '">', $report['subject'], '</a></strong> ', $txt['mc_reportedp_by'], ' <strong>', $report['author']['link'], '</strong>
mmm...
When do we actually expect not to have a board name there?
Any idea?