If I wanted to go ahead and cancel this (booked one to LAX) ... Is this possible? Not sure I want risk being reseated in coach or waiting for days for confirmation it will be honoured.

I booked thorugh Alitalia using Amex. Should I request refund from Amex on account I am unsure of whether it will be honoured properly ?

Even an if you think it will be honoured, appreciate anyone's advice on how to cancel.