Seems like this was a voluntary cancellation on your part as you didn't feel safe to contune onwards. No doubt the flight did continue to Pakistan with other paxs and obviously TG crew?
Marriott did provide some relief... But two separate organisations..
What were your expectations? That TG would go outside of the T&Cs that you and TG agreed to and provide a refund? Do the T&Cs say they will provide a refund in extenuating circumstances?