Magento2 ui component binding issue for file uploader in knockout template

Question

I am using knockout file uploader in one of checkout step, please check below screenshot:

below is my code to initialize file uploader but somehow its not working:

<div class="reference-document-upload-wrapper" id="reference-document-upload-wrapper" data-bind="scope: 'reference-document-uploader'" afterRender="refreshDiv">
     <!-- ko template: getTemplate() --><!-- /ko -->
</div>

<script type="text/x-magento-init">{".reference-document-upload-wrapper": {
                           "Magento_Ui/js/core/app": {
                               "components": {
                                   "reference-document-uploader": {
                                       "component": "Expresskitchen_OrderDocuments/js/form/element/file-uploader",
                                       "template": "ui/form/element/uploader/uploader",
                                       "allowedExtensions": "jpg jpeg gif png pdf doc docx xlsx xlx",
                                       "isMultipleFiles":true,
                                       "maxFileSize":2097152,
                                       "previewTmpl":"Expresskitchen_OrderDocuments/form/element/uploader/preview"

                                   }
                               }
                           }
                       }

}

this code is inside .html knockout template but somehow i cannot see browse button of file uploader, can anyone let me know how can i resolve this issue? i also tried to force apply knockout binding in its component js file but it did not work