Thanks,
I am not aware of an example.json, since it is also not listed in the itch.io project files and I do not have it in my cloud where the project is saved, are you sure it's part of this asset pack? There is an animation example but its a txt file, explaining which frames below to which animation.
As part of the
tilemap-selectedtiled-example.zip is an example.json included: Thats for opening with the tiled editor so you can see the tileset in action, and the example can be imported with any mayor engine. (Tiled is free and available on itch). Maybe it's that? :)
kind regards