Script EventKit to register a new Calendar event

With the help of Shane and others, I have assembled the following script that creates a new calendar event, and extracts a unique event identifier, referencing that event to insert into a Filemaker database.

I activate this applescript, after I have manually created a new event in the Calendar application, via that application’s user interface.

When activated, the Apple_ICal_Selected_Event objectForKey function returns an identifier.

However, unless I click on Application Calendar’s window outside of that new event, prior to activating this script, theEKEventStore’s eventWithIdentifier:Apple_ICal_Selected_Event will return no value. As such the applescript fails to return a unique EventKit event identifier of that Calendar EKEvent.

use scripting additions
use framework "Foundation"
use framework "EventKit"

set theEKEventStore to my initializeEventStore()
set NSEKEvent to missing value

set Apple_ICal_Selected_Event to (((current application's NSUserDefaults's alloc()'s ¬
	initWithSuiteName:"")'s ¬
	objectForKey:"SelectedEvents")'s ¬
	objectForKey:"iCal")'s ¬
# get theEKEventStore's database reference to a specific event by means of a localUID
set NSEKEvent to theEKEventStore's eventWithIdentifier:Apple_ICal_Selected_Event

set {theResult, theError} to theEKEventStore's saveEvent:NSEKEvent span:0 commit:true |error|:(reference)

on initializeEventStore()
	# Instatiate an EventKit Event Store to store a database of events 
	set theEKEventStore to current application's EKEventStore's alloc()'s init()
	# request access for theEKEventStore to access  Calendars
	theEKEventStore's requestAccessToEntityType:0 completion:(missing value)
	# obtain event store authorization status in regard to security permissions
	my authorizationStatus() --abort if no clearance; continue if  authorizationStatusForEntityType is 3
end initializeEventStore

on authorizationStatus()
	# check if app has access and authorization
	set authorizationStatus to current application's EKEventStore's authorizationStatusForEntityType:0 -- work around enum bug 
	if authorizationStatus is not 3 then
		display dialog "Access must be given in System Preferences" & linefeed & "-> Security & Privacy first." buttons {"OK"} default button 1
		tell application "System Preferences"
			tell pane id "" to reveal anchor "Privacy"
		end tell
		error number -128
	end if
end authorizationStatus

How can I script EventKit or Application “Calendar” to cause EventKit to register that new event, without having to manually click on Calendar’s window outside of that event field?