BCP Command to CSV/XLSX file with Merged Columns

Hi,

Currently i have written a BCP command to export query output to excel, which is working okay.

Now, Issue is I need to put a header (dynamic one) which will be placed on first row of excel and merge the columns to show data.

I know Merging columns in CSV file is not possible. and I am willing to create XLSX file. I even tried merging 2 excel files. which ended up in corrupt file. I am at dead end right now. 

Any help is much appreciated.

Thanks, Parth