Unfortunately, your colleague is making a basic error in spreadsheet design ... mixing raw data with analysis and presentation. Excel works best with simple tables of data. Given that, you can sort, filter, produce pivot tables and charts ... the world is your lobster.
But hey, it's his spreadsheet, you've told him why it's a problem, we've supported you and offered some solutions ... it's down to him how he moves forward, or continues to struggle. If it were me, I'd back away quietly.
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