Nong,
Not a defect enhancement request, would require and RFD excel extract extracts the data not heading as otherwise would get headings for each page.
The question to ask is why are they needing to export Debtors Transactions reports to Excel what is the business case behind the request to justify development change.
Dealer can learn to use report writer and create their own report as viable alternative as no other sites requesting this and not viewed as defect as it's designed that way.