I stumbled on an alternative solution when I couldn't get my scripts to run.

Create your excel file with all the sheets and the top row how you like it.

Make a copy of your file, this will just be the table structure.

In BIDS Create a File System task to delete the old file.

Create a second File System task to copy the table structure file and name DestinationConnection the same name as the deleted file.

If there's a chance someone will mess with the table structure file, make it hidden/write protected (you might need to the BIDS steps above before hiding it).

If you do end up changing the attributes of the table structure file, do a third file system task to change the attributes.