to answer the OP's question:
I have used FP products as part of a travel delay claim with Amex Canada. you need to show the original statement of the FP purchase (if made with the same card as the insurance is being claimed against) and the receipt; I also include the Flight credit statement and relevant itinerary, etc.
Key is that all expenses- and I mean all- for the trip in question have been made with the card covered by the insurance.