Did you catch that you are meant to save it in an older format not xlsx or xlsm just plain .xls before trying the hex editor? I'd iterate through the old formats from XL 97 to current and see if any of them have the value.
Here is something you haven't mentioned trying (removing "workbookProtection" tag in the XML): http://datapigtechnologies.com/blog/index.php/hack-into-a-protected-excel-2007-or-2010-workbook
Ah. I was doing something wrong. The passwordbreaker did work on the XLS. Thanks for all the responses. In case you think I've been lazy for the last 2 days. Yes, I tried saving to XLS. I also the zip technique , but I couldn't edit the XML file though it was clearly visible inside the my powerarchiver utility. Even explorer couldn't re-extract it out of the fake Zip. But hey, we're cooking with gas.
The perfect option formula. Enter a stock and it will output the option to buy for a 10x trade, xandman had been working on it for a few years and his efforts have finally paid off.
There's spreadsheet passwords for viewing security which is hard to break. The VBA passwords are more from tampering or accidentally deleting VBA objects.