The secret trick for importing data into Excel (without actually writing a file in the Excel file format): don't try CSV - as you have already noticed that will fail in all kind of fragile ways depending on your character encoding and operating system locale. Instead, convert your data into an html table and then paste or import that into Excel.

But not any html table, you need to have the appropriate proprietary css properties in there, such as the mso-data-placement:same-cell. Those are actually documented ...in the Office HTML and XML Reference published in 1999.