Actually, I am sure I just don't know how it works well enough to make it work, but hope the expertise here will be enough to correct my misdirection.

I am using xlUnique to find unique values comparing two spreadsheets' keys. I copy the range from each sheet into a new worksheet to do the compare as a continuous range instead of the scattered areas of an AutoFilter. Here is the code:
Code:
Private Function DataCorrect(ByRef woWkBk As Workbook, _
    ByRef ftpWkBk As Workbook, _
    ByVal endColumn As Long, _
    ByVal ftpMaxCol As Long, _
    ByVal psidColumn As Long, _
    ByRef exceptArray() As String, _
    ByRef sendDate As String, _
    ByVal errorSrc As String) As String

    Dim ftpWkSht As Worksheet
    Dim woWkSht As Worksheet
    Dim newWkSht As Worksheet
    Dim ftpRange As Range
    Dim woWkShtRange As Range
    Dim newRange As Range
    Dim formatCond As FormatCondition
    Dim ftpMax As Long
    Dim rowMax As Long
    Dim copyEnd As Long
    Dim rng2Strt As Long
    Dim rng2End As Long

    If Not ftpWkBk Is Nothing Then
        Set ftpWkSht = ftpWkBk.Sheets(1)
        If Not ftpWkSht Is Nothing Then
            With ftpWkSht
                ftpMax = .UsedRange.Rows.count
                Set ftpRange = .Range(.Cells(1, 1), .Cells(ftpMax, ftpMaxCol).End(xlUp))
                
                Set newWkSht = Sheets.Add(After:=Sheets(1))
                newWkSht.Name = tempShtName         ' Visual only
                Application.CutCopyMode = False     ' Clear clipboard of copied data
                
                ' Copy FTP PSIDs to new sheet for unique value filtering
                copyEnd = ftpMax - 1
                .Range("A2:A" & ftpMax).Copy Destination:=newWkSht.Range("A1", "A" & copyEnd)
                
                ' Copy Work Orders PSIDs to new sheet - find new start and end for range
                rng2Strt = copyEnd + 5
                rng2End = rng2Strt + rowMax
                woWkShtRange.Range("A2:A" & rowMax).Copy _
                    Destination:=newWkSht.Range("A" & rng2Strt, "A" & rng2End)
                
                ' Using both ranges, find any unique (not common to both) PSIDs
                Set newRange = newWkSht.Range("A1:A" & copyEnd & ",A" & rng2Strt & ":A" & rng2End)
                With newRange
                    .FormatConditions.AddUniqueValues
                    .FormatConditions(1).DupeUnique = xlUnique  ' xlUniqueValues
                    If .FormatConditions.count > 0 Then    ' <=== WORKS UP TO HERE, BUT CANNOT EXTRACT INFO
                        Set formatCond = .FormatConditions(1)
                        With .FormatConditions
                            For i = 1 To .count
                                ' Other code dealing with handling the unique value
                                  failReturn = WriteException(formatCond.item(i).Value, exceptArray, sendDate)
                                ' Other code dealing with handling the unique value
                           Next i
                        End With    ' .FormatConditions
                    Else
                        errString = " No mismatched rows in FTP/Work Orders "
                        failReturn = ProblemReport(errString, sendDate)
                    End If
                End With    ' newRange
            End With
            ' Other code copying values from one DB to another
                
            Application.DisplayAlerts = False       ' Suppress "SaveAs" dialog box
            Application.EnableEvents = False        ' Suppress BeforeSave event
            newRange.FormatConditions.Delete
            newWkSht.Delete
            ftpWkBk.Save
            Application.EnableEvents = True
            Application.DisplayAlerts = True
            DataCorrect = "Success"
        Else
            ' error checking removed for posting
        End If
    Else
        ' error checking removed for posting
    End If
End Function
To summarize, I successfully create the .FormatConditions collection, but cannot extract the values the .FormatCondition identifies.