Looking at the JSON response data you posted, the object locator for the schedule has the schedule-task object as its last element (the item within the orange rectangle below). The id of the directory containing the schedule is highlighted in the blue rectangle. This is also the last item in the search path.
However, the container object in the 'Get list of directories' API call you posted also includes this element.
The 'Get list of directories' API returns the list of directories in the specified container. Have you created a sub-directory within the specified directory - if you are already at the lowest level in that directory structure the API will not return any directory information.
Note that the Data360 Analyze REST APIs are only supported for Server editions of the product.