Use Script Apps to modify the response of one form element directly (programmatically) rather than use the urlj edit response

I am using a form to collect booking details and attach a script to the form (so the form submit trigger will fire when a response is edited that is not allowed for the spreadsheet version) that sends an email, schedule calendar events, generates supporting documents, etc. .d. on the form submit. By using if statements, I have provided the user with the option to avoid "clicking the button to not send the email function to the client" so that the form responses can be edited without triggering the automatic functions, but this is up to the user who wants to click those boxes. A better solution would be to have the script as its final function, change the response of the element, so that when the form is edited in the future, the automatic functions are already disabled.

I don't want to create a new form response (although it would be possible to customize the predefined url to create a duplicate with appropriate changes)

FormResponse.withItemResponse (response) indicates that it does not work with stored responses

It's so easy to view the responses in the form, and with the built-in edit response url function, I figured editing a single item response would be doable, but so far it has eluded me.

Is there a way to do this?

thank