Paste the returned json data into the left hand column here: http://jsonpathfinder.com/ (deleting the example data first).
Drill down in the right hand column until you get to the data you want. Paste the result in the top of the right hand column here and I’ll try to format it sensibly for HA if you need help.
The problem is it won’t be in the result as I have just asked for the total number of movies with the VideoLibrary,.GetMovies request. You can let Kodi do all the hard work by adding filters to get your desired array returned, like [playcount]. I just can’t tell how to structure it in the kodi.call_method