I am the developer of the JSON Feed Manager Software that Donp88 mentions in this post. If you haven't already, I'd suggest you take a look at the
demo I've provided and the
tutorial video I've created. The software
does not require any knowledge of JSON syntax. It creates and manages syntactically correct JSON feed files for you. There's no subscription fees, and, I provide free support and maintenance updates.
Windows desktop software for creating and managing MRSS, JSON, and FireTV feeds @ https://rrirower.wixsite.com/software. No Programming, JSON or MRSS knowledge required.