Hi,
The reason the plugin isn’t passing parameters to your iframe is because it has two IDs:
<iframe id="JotFormIFrame-92191354922862 rwcGetParams" style="width: 1px; min-width: 100%; height: 539px; border: none;" title="Custom Webview" src="https://form.jotform.co/92191354922862?test='test'" frameborder="0" scrolling="no" allowfullscreen="allowfullscreen"><br />
</iframe>
HTML elements can only have one ID – the browser will only render the first ID and ignore anything else. You need to remove JotFormIFrame-92191354922862 from your iframe id to get the plugin to work.
RE getting multiple parameters from the URL, yes, that will work – it will pass all parameters that are in the URL to the iframe.