DOMPDFModule无法正确呈现字段

我正在尝试通过DOMPDFModule for Zend Framework 2渲染PDF文档。在大多数情况下，它可以成功渲染，但是字段已关闭。这是我的控制器和视图代码：

 public function pdfAction()
 {
    $pdf = new PdfModel();
    $pdf->setOption('filename', 'questions');
    $pdf->setOption('paperSize', 'a3');
    $pdf->setOption('paperOrientation', 'landscape');

    $pdf->setVariables(array(
        'records' => $this->getQuestionsService()->getRecords()
    ));

    return $pdf;
 }

和视图-

  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" type="text/css">

<div class="container">
    <div class="row">
        <div class="col-md-6">
            <img src="http://dev.teeforall.com/images/logo.png">
        </div>

        <div class="col-md-6">
            <h1>Questions Report</h1>
        </div>
    </div>
</div>


    <table class="table table-striped table-hover table-bordered">
            <tr>
                <td>Id</td> <!-- 0 -->
                <td>Question</td> <!-- 1 -->
                <td style="white-space: nowrap;">Order Issue</td> <!-- 2 -->
                <td style="white-space: nowrap;">Shipping Issue</td> <!-- 3 -->
                <td style="white-space: nowrap;">Refunds/Returns Issues</td><!-- 4 -->
                <td style="white-space: nowrap;">Update Issues</td> <!-- 5 -->
                <td style="white-space: nowrap;">Campaign Issue</td> <!-- 6 -->
                <td style="white-space: nowrap;">Change Issues</td> <!-- 7 -->
                <td style="white-space: nowrap;">Design Issues</td> <!-- 8 -->
                <td style="white-space: nowrap;">TeeForAll Works</td> <!-- 9 -->
                <td style="white-space: nowrap;">Order ID</td> <!-- 10 -->
                <td style="white-space: nowrap;">Site url</td> <!-- 11 -->
                <td>Name</td> <!-- 12 -->
                <td>Email</td> <!-- 13 -->
                <td>Comment</td> <!-- 14 -->
                <td>Status</td> <!-- 15 -->
            </tr>

            <?php 


                if (false !== $this->records) {
                    foreach ($this->records as $records): ?>

                    <tr>
                        <td><?php echo $records->id; ?></td> <!--  0 -->
                        <td><?php echo $records->question; ?></td> <!-- 1 -->
                        <td><?php echo $records->order_issue; ?></td> <!-- 2 -->
                        <td><?php echo $records->sub_shipping_issue; ?></td> <!-- 3 -->
                        <td><?php echo $records->sub_refunds_returns_issue; ?></td> <!-- 4 -->
                        <td><?php echo $records->sub_update_issue; ?></td> <!-- 5 -->
                        <td><?php echo $records->sub_campaign_issue; ?></td> <!-- 6 -->
                        <td><?php echo $records->sub_campaign_change_issues; ?></td> <!-- 7 -->
                        <td><?php echo $records->sub_campaign_design_changes; ?></td> <!-- 8 -->
                        <td><?php echo $records->sub_teeforall_works; ?></td> <!-- 9 -->
                        <td><?php echo $records->order_id; ?></td> <!-- 10 -->
                        <td><?php echo $records->site_url; ?></td> <!-- 11 -->
                        <td><?php echo $records->name; ?></td> <!-- 12 -->
                        <td><?php echo $records->email; ?></td> <!-- 13 -->
                        <td><?php echo $records->comment; ?></td> <!-- 14 -->
                        <td><?php echo $records->status; ?></td> <!-- 15 -->
                    </tr>
                <?php endforeach; ?>

                <?php } else {  ?>

                    <tr>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                        <td>null</td>
                    </tr>
                <?php 
                      }
                ?>
    </table>

这是获取数据库条目的实际代码：

 /**
 * Gets all rows from the database table questions
 * @return ResultSet|bool
 */
public function getRecords()
{

    $sql_select = new Select('questions');

    $sql_select->columns(array(
        'id', 'question', 'order_issue', 'sub_shipping_issue', 'sub_refunds_returns_issue', 'sub_update_issue',
        'sub_campaign_issue', 'sub_campaign_change_issues', 'sub_campaign_design_changes', 'sub_teeforall_works', 'order_id', 
        'site_url', 'name', 'email', 'comment', 'status'
    ))->where(new \Zend\Db\Sql\Predicate\IsNotNull('id'));


    $select = $this->table_gateway->selectWith($sql_select);

    if ($select->count() > 0) {
        return $select;
    }

    return false; 

}

另外，以下图像可能最能描述我想说的内容：

如您所见，这些字段相差一（在id字段中应该有15个），依此类推。

任何帮助，将不胜感激。

谢谢！