I'd like to create a few lines of header info like on the attached image. Below is the code that exports my table to Excel. How can i create the 3 lines of text?

   $title=sprintf("proforma 6765 for %s. warning: this spreadsheet is just a sample and should not be relied upon without expert due diligence",$this->session->userdata('campaign'));
        $description=sprintf("Sample of 6765");
        $report = new MyExport6765;
        $report->run()->exportToExcel(array(
            "properties" => array(
                "creator" => "Research Study Online",
                "title" => $title,
                "description" => $description,
                "subject" => "sample 6765",
                "keywords" => "",
                "category" => "",
            )
        ))->toBrowser($this->session->userdata('campaign') . " sample 6765.xlsx");