Sort command for a .txt file not operating in a VBA Shell

I believe I've replicated the stachoverflow recommended code to sort a .txt file using VBA in Excel. The following is the relevant code from my program. It processes this code without error but does not produce the sorted output file. The IntualityInputRealTimeFIFOTable file is produced correctly. Can't figure out what I'm doing wrong.

Public MyCommand As String
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IntualityInputRealTimeFIFOTable = WorkbookPath & "IntualityInputRealTimeFIFOTable.txt"
IntualityInputRealTimeFIFOTableTemp = WorkbookPath & "IntualityInputRealTimeFIFOTableTemp.txt"
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Close #3
MyCommand = "Sort IntualityInputRealTimeFIFOTable /O IntualityInputRealTimeFIFOTableTemp"
Shell MyCommand, vbHide