If you are exhibiting the customer symptoms described in a tsb, it is covered under warranty. If you are not exhibiting symptoms of a tsb, and you tell them to perform the tab flash anyway, you have to pay yourself. Since your VIN is listed as an RSU, I would see if they can double check your vehicle and see if you are owed a refund for paying out of pocket.
When they hook up to your truck, they will see a topography screen of all the modules on the vehicle, similar to the pic below. Any modules that have an available flash will show the green circle with white flash bolt.
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