We ran into a problem trying to use the code, and found this fix to get it working.  Hope this helps someone else out...

Earlier in the code it tries to call .getFeedInfo()  on the NotesDataService instance and was bombing out.   No, data was being returned.

So, I changed this:

function NotesDataService()
{
    
    /**
     * Get feed information, like title, link, ...
     */
    this.prototype = function()

to this:

function NotesDataService()
{
    
    /**
     * Get feed information, like title, link, ...
     */
    this.prototype.getFeedInfo = function()