Is the API set up correctly to trigger shipping notification emails?

Need confirmation on the API call that we have if this is correctly set up to trigger shipping notification emails (shipping confirmation & delivery confirmation) or if the “false” needs to be “true”? Is there anything else we need to do to trigger these?

{“fulfillment”:{“message”: “The package was shipped this morning.”,“notify_customer”: false,“tracking_info”:
{ “number”: “1Z8R8V330390982616”, “company”: “” },
“line_items_by_fulfillment_order”:[{“fulfillment_order_id”:5374249828465,“fulfillment_order_line_items”:[{“id”: 11286276636785, “quantity”:1}]}]}}

Similarly, we are also not seeing order cancelation emails triggering. This is the call that we currently have:

https://save-the-duck.myshopify.com/admin/api/2021-10/orders/4320927350897/cancel.json