What is happening is when Power Query in Power BI imports the text in this Excel file, the data in being converted to ASCII symbols at the import. The user cannot modify this behavior. So data that looks like this:
is converted to this on the SOURCE line - no transformations were done, it was just imported incorrectly.
Note that if you open the Excel file and use Excel's Power Query to import the data, it is imported correctly. I have confirmed there are no formatting issues in the original excel file. copying all data to a new file as text only does not fix the issue.