A redline error/incomplete listing error exists because you have no product listing tied to your FBA inventory item yet.
Each of your FBA MSKUs has its own designated FNSKU barcode for labeling. Each time you save an item to a batch in Stratify, a small amount of data is sent to Amazon in order to allow an FNSKU to be created so your product label can successfully print.
If you have not yet gotten to the point with your batch where product feeds have been set or have not waited the amount of time for the feeds to complete their send (up to 30 minutes), you will see this type of error in Seller Central.
For Private batches, feeds are sent when clicking the Sync button on the Review Batch page.