In that fiddle you are doing the parsing with AlaSQL. AFAIK that library doesn't support xlsm.
I would instead opt for SheetJS (you are including that in the fiddle, too, for some reason). SheetJS can handle
xlsm files quite nicely. Here is a demo. If you drop an
xlsm file onto the rectangular box on that page, you'll see the data is parsed as expected.
You can inspect the page's source code to get an idea how to use it.