I cannot find where the Promoted Listing Fees and Discounts & Credits are broken down anywhere on Ebay's interface. We had our accountant trying to reconcile credit card charges for a client and it's been a nightmare.
We've determined eBay's invoice is pieced together this way.
Their "Total Due" consists of :
1. + Final Value Fees
2. + Subscription Fees
3. + Promoted Listing Fees
4. - Discounts and Credits
Final Value Fees and Subscription fees are straightforward, the rest not so much.