Fulfillment Export (Fulfill Prime orders directly from inside of NetSuite)
You will need to update your Fulfillment flow Saved Search in NetSuite to ignore the SFP orders i.e. add the filter "is Prime" equals to false.
Then to do the fulfillment, you are required by Amazon to buy shipping labels from Amazon itself. This functionality is not automated by the Integration App currently. You can either handle it manually by generating the Shipping labels right from the Amazon interface (recommended if you only have low volumes or just starting out) OR sign up for a Shipping Provider to integrate with Amazon and that way generate labels from inside of NetSuite.