Hmm, well that all looks ok. What do you have for your entire $sql for the quick stats?
Mine: (which may include changes for MODs - I'm not sure at this point)
$sql='SELECT count(open.ticket_id) as open, count(answered.ticket_id) as answered '.
',count(overdue.ticket_id) as overdue, count(assigned.ticket_id) as assigned '.
' FROM '.TICKET_TABLE.' ticket '.
'LEFT JOIN '.TICKET_TABLE.' open ON open.ticket_id=ticket.ticket_id AND open.status=\'Open\' AND open.isanswered=0 '.
'LEFT JOIN '.TICKET_TABLE.' answered ON answered.ticket_id=ticket.ticket_id AND answered.status=\'Open\' AND answered.isanswered=1 '.
'LEFT JOIN '.TICKET_TABLE.' overdue ON overdue.ticket_id=ticket.ticket_id AND overdue.status=\'Open\' AND overdue.isoverdue=1 '.
'LEFT JOIN '.TICKET_TABLE.' assigned ON assigned.ticket_id=ticket.ticket_id AND open.status=\'Open\' AND assigned.staff_id='.db_input($thisuser->getId());