GemBox.Spreadsheet does not use Microsoft Excel to calculate positions and sizes of elements on the page, therefore the results might not be identical since the Excel’s layout/rendering engine is not standardized nor its code is open.
GemBox.Spreadsheet, just like any other Excel application, uses its own layout/rendering engine to paginate and render the spreadsheet’s content. We do not have Excel’s rendering engine source code, no one does, but we do try to provide the exact calculations as much as possible.
However, again I’m afraid that some differences may occur. Also, the differences may occur with other Excel applications as well like OpenOffice Calc, LibreOffice Calc, Microsoft Excel for Mac, etc.
For instance, if you export that “test.xlsx” file to PDF with LibreOffice Calc you’ll get 56 rows.
Anyway, perhaps you should consider explicitly specifying horizontal and vertical page breaks? That way you would define exactly where you want the page breaks to occur.