Breach time in minutes is most likely an "After Read" calculation. After Read calculations are not saved to the database upon calculating. If you tried to pull the data directly with a SQL query for example, there would be nothing there. As such After Read calculated values cannot be used to sort column data. This can be fixed somewhat by changing the calculation to a "Before Save" calculation, but that calculation then must have a dependency field set to trigger the calculation to reevaluate and the data will then be saved to the database and may not be useful if saved long term.
After posting I found almost the exact same question with a more detailed solution https://community.landesk.com/thread/34328
This solution should work in the OOTB and should get you what you need.
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