How to order in a "row grouping" by date?

PatricioFink

From: https://datatables.net/examples/advanced_init/row_grouping.html

I have a table where i'm grouping by date:

http://s9.postimg.org/6dkbxsibz/Capture.jpg

but when i try to order by that grouping row, it gets ordered by the TIME and not the DATE:

http://s24.postimg.org/c8n1cu2c5/Capture.jpg

This is my script:

 $(function () {
        
        var table = $('#VentasLocacion').DataTable({
            "columnDefs": [
                { "visible": false, "targets": 0 }
            ],
            "order": [[0, 'desc']],
            "displayLength": 100,
            "drawCallback": function (settings) {
                var api = this.api();
                var rows = api.rows({ page: 'current' }).nodes();
                var last = null;

                api.column(0, { page: 'current' }).data().each(function (group, i) {
                    if (last !== group) {
                        $(rows).eq(i).before(
                            '<tr class="group"><td colspan="7"><b>' + "Fecha de venta: " + '</b>' + group + '<b>' + " Cliente: " + '</b>' + rows[i].children[3].innerText + '</td></tr>'
                        );

                        last = group;
                    }
                });
            }
        });


        // Order by the grouping
        $('#VentasLocacion tbody').on('click', 'tr.group', function () {
            var currentOrder = table.order()[0];
            if (currentOrder[0] === 2 && currentOrder[1] === 'asc') {
                table.order([2, 'desc']).draw();
            }
            else {
                table.order([2, 'asc']).draw();
            }
        });

    });