Do you deploy the SwiftDialog app on the machine before hand?  SwiftDialog installs an app called dialog so it can run.  Essentially all commands are sent to that app so they can run.  

I have the same exact issue. 

hi all.. seeing the same here with notifications when called via script in JAMF

OSvers 13.1 / 13.2 

swiftdialog 2.1 pkg installed fine.. and all works lovely from local CLI 

now there is this.. https://github.com/bartreardon/swiftDialog/issues/219  

I have config profile installed.. swiftDialog.Banners.mobileconfig.zip

and have tried both direct call from script as root, and also by calling 'dialog' via 'su' with logged in user.. still getting the same error... 

Notifications are not available: Couldn’t communicate with a helper application. Check to see if Notifications for Dialog.app are enabled in notification center

what am I missing? 

Let me know if you find any solution, thanks

This is now fixed and working for me on 12.x and 13.x 

use version 2.1 of swift dialog (this mitigates call as root using the script in /usr/local/bin/dialog) so use this in your scripts.. 

change the config profile to this (disable critical alerts)