Row grouping with printing

I believe i solved the problem with printing with row grouping. I found a snippet of code on StackOverflow here and was able to fix it up to work with row grouping. This is placed in datatable-buttons.js on line 1564.

Heres some images of it working!
http://prntscr.com/fhx1vu
http://prntscr.com/fhx1ia

    var _exportData = function ( dt, inOpts )
    {

        var config = $.extend( true, {}, {
            rows:           null,
            columns:        '',
            grouped_array_index: [],
            modifier:       {
                search: 'applied',
                order:  'applied'
            },
            orthogonal:     'display',
            stripHtml:      true,
            stripNewlines:  true,
            decodeEntities: true,
            trim:           true,
            format:         {
                header: function ( d ) {
                    return strip( d );
                },
                footer: function ( d ) {
                    return strip( d );
                },
                body: function ( d ) {
                    return strip( d );
                }
            }

        }, inOpts );

        var strip = function ( str ) {
            if ( typeof str !== 'string' ) {
                return str;
            }

            // Always remove script tags
            str = str.replace( /<script\b[^<]*(?:(?!<\/script>)<[^<]*)*<\/script>/gi, '' );

            if ( config.stripHtml ) {
                str = str.replace( /<[^>]*>/g, '' );
            }

            if ( config.trim ) {
                str = str.replace( /^\s+|\s+$/g, '' );
            }

            if ( config.stripNewlines ) {
                str = str.replace( /\n/g, ' ' );
            }

            if ( config.decodeEntities ) {
                _exportTextarea.innerHTML = str;
                str = _exportTextarea.value;
            }

            return str;
        };


        var header = dt.columns( config.columns ).indexes().map( function (idx) {
            var el = dt.column( idx ).header();
            return config.format.header( el.innerHTML, idx, el );
        } ).toArray();

        var footer = dt.table().footer() ?
            dt.columns( config.columns ).indexes().map( function (idx) {
                var el = dt.column( idx ).footer();
                return config.format.footer( el ? el.innerHTML : '', idx, el );
            } ).toArray() :
            null;

        var rowIndexes = dt.rows( config.rows, config.modifier ).indexes().toArray();
        var selectedCells = dt.cells( rowIndexes, config.columns );
        var cells = selectedCells
            .render( config.orthogonal )
            .toArray();
        var cellNodes = selectedCells
            .nodes()
            .toArray();

        var grouped_array_index     = config.grouped_array_index;                     //customised
        var no_of_columns           = header.length;
        var no_of_rows              = no_of_columns > 0 ? cells.length / no_of_columns : 0;
        var body                    = new Array( no_of_rows );
        var body_data               = new Array( no_of_rows );                                //customised
        var body_with_nodes         = new Array( no_of_rows );                          //customised
        var body_with_nodes_static  = new Array( no_of_rows );                          //customised
        var cellCounter             = 0;

        for (var i = 0, ien = no_of_rows; i < ien; i++)
        {
            var rows            = new Array( no_of_columns );
            var rows_with_nodes = new Array( no_of_columns );

            for ( var j=0 ; j<no_of_columns ; j++ )
            {
                rows[j]             = config.format.body( cells[ cellCounter ], i, j, cellNodes[ cellCounter ] );
                rows_with_nodes[j]  = config.format.body( cellNodes[ cellCounter ], i, j, cells[ cellCounter ] ).outerHTML;
                cellCounter++;
            }

            body[i]                     = rows;
            body_data[i]                = rows;
            body_with_nodes[i]          = $.parseHTML('<tr class="even">'+rows_with_nodes.join("")+'</tr>');
            body_with_nodes_static[i]   = $.parseHTML('<tr class="even">'+rows_with_nodes.join("")+'</tr>');
        }

        /******************************************** GROUP DATA *****************************************************/
        var row_array                       = dt.rows().nodes();
        var row_data_array                  = dt.rows().data();
        var iColspan                        = no_of_columns;
        var sLastGroup                      = "";
        var inner_html                      = '',
            grouped_index;
        var individual_group_array          = [],
            sub_group_array                 = [],
            total_group_array               = [];
        var no_of_splices                   = 0;  //to keep track of no of element insertion into the array as index changes after splicing one element

        for (var i = 0, row_length = body_with_nodes.length; i < row_length; i++)
        {
            sub_group_array[i]              = [];
            individual_group_array[i]       = [];

            var sGroup                      = '';

            for(var k = 0; k < grouped_array_index.length; k++)
            {
                sGroup                          = row_data_array[i][grouped_array_index[k]];
                inner_html                      = row_data_array[i][grouped_array_index[k]];
                grouped_index                   = k;
                individual_group_array[i][k]    = row_data_array[i][grouped_array_index[k]];
                sub_group_array[i][k]           = sGroup;
            }

            total_group_array[i] = sGroup;


            console.log("grouped_index",grouped_index);

            if ( sGroup !== sLastGroup )
            {
                var table_data              = [];
                var table_data_with_node    = '';

                for(var $column_index = 0;$column_index < iColspan;$column_index++)
                {
                    if($column_index === 0)
                    {
                        table_data_with_node        += '<td style="border-left:none;border-right:none">'+inner_html+'</td>';
                        table_data[$column_index]   = inner_html + " ";
                    }
                    else
                    {
                        table_data_with_node        += '<td style="border-left:none;border-right:none"></td>';
                        table_data[$column_index]   = '';
                    }
                }

                body_with_nodes.splice(i + no_of_splices, 0, $.parseHTML('<tr class="group group_'+grouped_index+' grouped-array-index_'+grouped_array_index[grouped_index]+'">'+table_data_with_node+'</tr>'));
                body_data.splice(i + no_of_splices, 0, table_data);
                no_of_splices++;
                sLastGroup = sGroup;
            }
        }

        return {
            header: header,
            footer: footer,
            body:   body_data
        };
    };

Usage:
Define grouped_array_index in exportOptions

 exportOptions: {
        // Any other settings used
        grouped_array_index: [<place row to use here>],
 },