Carrier Guarantees - Shipment Transit Time Verification - Shipment Audit
FedEx and UPS offer Guaranteed delivery that include refunding shipping cost to the Shipper if a shipment is late. This is requesting that ShipStation incorporate a function that would identify those shipments that we can request refunds for.
(Even USPS Express offers guaranteed delivery)
There are other companies that will "Audit" guaranteed delivery estimates for a percentage of the shipping fees they recover. I do not see any reason you cannot incorporate something similar into your shipping solution. It could just be something we opt into that you get a piece of the pie. Or, if there is some "no cost" option that you could offer that just identifies possible shipments that might qualify for the refunds.
I believe this is something that you should offer to us as your customers - I would much rather have everything in one place.