Delete the oldest repeat

Assuming that the records are already ordered by date (i.e. oldest to newest), this might work for you:

Option Explicit
Public Sub FixBaseData()

Dim lastRow As Long
Dim thisRow As Long
Dim lookupTable As Object
Dim lookupKey As Variant

' Create the lookup table
Set lookupTable = CreateObject("Scripting.Dictionary")

' Find the last row of data
lastRow = Cells(Rows.Count, "A").End(xlUp).Row

' Temporarily turn off the screen updating
Application.ScreenUpdating = False

' Process from the latest record (at the bottom) to the oldest (at the top)
For thisRow = lastRow To 2 Step -1
    ' If the result isn't "Passed" then delete the row
    If Cells(thisRow, "I").Value <> "Passed" Then
        Cells(thisRow, "A").EntireRow.Delete xlShiftUp
    Else
        ' Create a key for the lookup table based on the first and second names
        lookupKey = Cells(thisRow, "E").Value & " " & Cells(thisRow, "F").Value
        
        ' Have we seen this name already?
        If lookupTable.Exists(lookupKey) Then
            ' Yes - delete the row
            Cells(thisRow, "A").EntireRow.Delete xlShiftUp
        Else
            ' No - add the name to the lookup table
            lookupTable.Add lookupKey, lookupKey
        End If
    End If
Next thisRow

' Restore screen updating
Application.ScreenUpdating = True

End Sub

Suggest you run it on a copy of your base data!

WBD

Here's another option. It assumes the data is already sorted by column B descending. If not just add another instruction to the macro to sort it first.

In general I prefer to avoid loops since they can be very time consuming and it's the most efficient way I know to do this sort of stuff.

This approach :

A. Identifies the number of Rows
B. Creates helper column J which concatenates the last/First name
C. Creates a formula in column K which identifies a duplicate name or <> "Passed"
D. Filters column K for the word 'delete'
E. Stops Excel halting to alert you about deleting
F. Deletes all the filtered rows
G. Removes the filter
H. Deletes the helper columns J & K

Sub DeleteStuff()
    Dim lRow As Long
    lRow = Sheet1.Range("A" & Rows.Count).End(xlUp).Row  'A

    Range("J2:J" & lRow) = "=F2&"" ""&E2" 'B
    Range("K2:K" & lRow) = "=IF(OR(I2<>""Passed"",COUNTIF(J$2:J2,J2)>1),"" delete"","" "")" 'C
    Range("K2:K" & lRow).AutoFilter field:=1, Criteria1:="delete" 'D
    Application.DisplayAlerts = False 'E
    Range("K2:K" & lRow).SpecialCells(xlCellTypeVisible).Rows.Delete 'F
    Range("K2").AutoFilter 'G
    Range("J:K").EntireColumn.Delete 'H

End Sub

You could do that or you could use this modified version:

Option Explicit
Public Sub FixBaseData()

Dim lastRow As Long
Dim thisRow As Long
Dim lookupTable As Object
Dim lookupKey As Variant
Dim ws As Worksheet

' Get a reference to the worksheet
Set ws = Worksheets("Base Data")

' Create the lookup table
Set lookupTable = CreateObject("Scripting.Dictionary")

' Find the last row of data
lastRow = ws.Cells(ws.Rows.Count, "A").End(xlUp).Row

' Temporarily turn off the screen updating
Application.ScreenUpdating = False

' Process from the latest record (at the bottom) to the oldest (at the top)
For thisRow = lastRow To 2 Step -1
    ' If the result isn't "Passed" then delete the row
    If ws.Cells(thisRow, "I").Value <> "Passed" Then
        ws.Cells(thisRow, "A").EntireRow.Delete xlShiftUp
    Else
        ' Create a key for the lookup table based on the first and second names
        lookupKey = ws.Cells(thisRow, "E").Value & " " & ws.Cells(thisRow, "F").Value
        
        ' Have we seen this name already?
        If lookupTable.Exists(lookupKey) Then
            ' Yes - delete the row
            ws.Cells(thisRow, "A").EntireRow.Delete xlShiftUp
        Else
            ' No - add the name to the lookup table
            lookupTable.Add lookupKey, lookupKey
        End If
    End If
Next thisRow

' Restore screen updating
Application.ScreenUpdating = True

End Sub

WBD