jQuery Custom Events not Registered in $( document ).ready()

Question

I am registering custom event handlers using .on() in $(document).ready() but they are not being triggered.

I have verified in both Chrome and Firefox that

1. The events are being registered to the correct elements,
2. The handler is working correctly,
3. The even is being triggered on the correct elements

I've also registered the same handler under a built-in event (e.g. click) and everything works perfectly.

I tried to create a minimum working example, but haven't been able to replicate this behavior.

Of Relevance

• Everything works in jQuery 1.12.4, but not in 3.2.1
• The code is being run as part of a custom WordPress 4.9.1 plugin
• Test Page
• Full Code
• The custom event is named eor:date-change
• The event is registered and triggered on .eor-calendar elements
• The basic logic flow is a user clicks on a navigation button ( .eor-nav ) which sets the date on the calendar ( .eor-calendar ) via the data-current-date attribute. The eor:date-change event is then triggered which updates the dates on the calendar, and triggers an eor:appointment-change event on each of the appointments. The appointments then update their data accordingly.

Relevant Code

$( document ).ready( function( ) { 
    $( '.eor-calendar' ).on( 'eor:date-change', function() {
        eor_updateCalendarToCurrentDate( $( this ) );
    } );
} );

function eor_setCalendarDate( date, calendar, timezone ) {
    var $ = $ || jQuery;

    if( ! ( date instanceof Date ) ) {
        date = new Date( date );
    }
    if( ! calendar ) {
        calendar = $( '.eor-calendars-wrapper .eor-calendar' );
    }

    calendar.each( function() {
        var self = $( this );
        var startDate = eor_stringToDate( self.data( 'start-date' ), timezone );
        var endDate = ( self.data( 'end-date' ) ? eor_stringToDate( self.data( 'end-date' ), timezone ) : undefined );

        if( startDate <= date ) { 
            if( ! endDate || date <= endDate ) { 
                // set date
                var dateString = eor_dateToString( date ); 
                self.attr( 'data-current-date', dateString );
                self.data( 'current-date', dateString );

                // trigger event to update calendar
                self.trigger( 'eor:date-change' ); 
            }
        }
    } );
}

Update 1 When checking the jQuery version ($.fn.jquery) I get

3.2.1 -ajax,-ajax/jsonp,-ajax/load,-ajax/parseXML,-ajax/script,-ajax/var/location,-ajax/var/nonce,-ajax/var/rquery,-ajax/xhr,-manipulation/_evalUrl,-event/ajax,-effects,-effects/Tween,-effects/animatedSelector

Perhaps the functionality I need has been removed by WordPress. If this is the case how can I include it?