How to change failure info in Testlist's Excel Result

I ran the testlist base on those code
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//Verify Edit screen is not Applied with Customisation
 obr.objControls.FrameMain.WaitForElement(Common.MaxTimeout, "id=btnEdit");
 obr.objControls.FrameMain.Find.ById<HtmlInputSubmit>("btnEdit").Click();
 CommonFunction.RefreshFrame(obr.frameMainInfo);
 obr.objControls.FrameMain.WaitForElement(Common.MaxTimeout, "id=mplblTableKeyLabel");
 bool checkEditScreen = obr.objControls.FrameMain.Find.ById<HtmlSpan>("mplblTableKeyLabel").InnerText == "Key";
 Assert.IsTrue(checkEditScreen, checkEditScreen ? "" : "The customisation of 'Key' was applied to Edit screen");
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            And the failure info in log file is
Failure Information:
~~~~~~~~~~~~~~~
Exception thrown executing coded step: '[Step3] : Verify lookup table label 'key' can now be renamed via Terminology Manager and the customisation is applied throughout the system'.
InnerException:
ArtOfTest.Common.Exceptions.AssertException: The customisation of 'Key' was applied to Edit screen - [Expected:True],[Actual:False]
            When  I get the Excel Result  the Failure info is
"Exception thrown executing coded step: '[Step3] : Verify lookup table
label 'key' can now be renamed via Terminology Manager and the
customisation is applied throughout the system'. "

           And i want to get the exception info "The customisation of 'Key' was applied to Edit screen - [Expected:True],[Actual:False]" to the Excel report . Can you give me a way to do it. Thank you.