you are not considering that multiple values are set under request_date (and also the others fields of the form), try to simply print_r() that variable: <?php print_r($_POST['request_date']); ?> and you will see an array with a value for each report form, so if there are three reports you will have three request_date values. At the moment you get six different arrays from your form and you need to create a single array, like in this example:
Array (  => a  => aa ) # first group
Array (  => b  => bb ) # last group
At this point you need only to insert:
mysql_query("insert into table ('field_A','field_B') $neworder");
In order to make it work with your class, you can: send a single array (reordered) to addReport() instead of single strings just like in my first example (I think you will need to serialize* data to get the array inside the function and unserialize to get it to work again) and finally create a loop to sanitize each value and, similarly to my second example, create the values() part of the insert string.