Can I use TVMLKit without using JS javascript?

I have access to a website which contains videos and an existing .js description file. The website is serving videos for a different platform, and the .js file has all the information such as content type, video URL, description, img URL that I need. But I can't get that information translated on the website to TVML format.

I would like to create an app to display the content on AppleTV, and later on iOS devices, so prefer not to learn and use Javascript.

Initially I will use TVMLKit, so I would like to retrieve the .js file but then handle it programmatically in Swift, translating the various content into XML format and then pushing the document using navigationDocument.pushDocument() - if that is available outside javascript.

Is this possible?

When I start up a tvOS project, it always wants to retrive the web data through a javascript call, rather than a URL Session. Can I avaoid this?