Excel Export Add Rows and Data

Hello everyone,

i am now trying to modify the table before saving it as EXCEL and i don't know how to add two sentences before the table starts. For example add one new row before the table and input there a text. I am now using the following code to make the column G blue. I can use the customize ability, but no idea how

    buttons: [{
                        extend: 'excel',
                        text: 'Save in EXCEL',
                        filename: 'td900',
                        customize: function(xlsx) {
                            var sheet = xlsx.xl.worksheets['sheet1.xml'];
                           // $('c[r=A1] t', sheet).text( 'Custom text' );

                            // Loop over the cells in column `F`
                            $('row c[r^="G"] ', sheet).each( function () {
                                // Get the value and strip the non numeric characters

                                   if ( $( this).text() !== "needed Adjustment" ) {
                    $(this).attr( 's', '20' );
                }

                            });
                        }


                            }]