Use Case: When you create an RMA from a Sales Order in Netsuite of an order with a Serialized Inventory Item the serial numbers don't carry over to the RMA. So, you can't receive a Serialized Inventory Item with no serial numbers from the RMA. Thus, it doesn't work. If you make up serial numbers to receive on the Sales Order RMA they get received at $0.00. If you create an RMA from an INVOICE the serials carry over and are received at a cost.
Solution: The Invoice must have all the data that is on the Sales Order. The eTail order line ID, eTail Order ID, and eTail Channel must be set on the Invoice too. We can achieve this by updating the mapping on Jet Return to NetSuite Return Authorization Add. We have a look up for Created From field. Instead of Sales Order, we search for Invoice record.