I can sanitise the last version a bit and come up with a simple function to get you an array of your missings, where the function takes the unique name, ( the unique name in the test data is the things like aa bb cc etc. )

Code:
Sub SlightlySanerVersion()
Dim arrStrTemp() As String: Let arrStrTemp() = Split(Mid(Replace("#" & Join(Application.Index(Evaluate("=IF(ISERROR(MATCH(F2:F463,C2:C463*($A$2:$A$1000=$I$1),0)*($A$2:$A$1000=$I$1)),ROW(F2:F463),0)"), Evaluate("=column(A:QT)"), Evaluate("=column(A:QT)/column(A:QT)")), "#"), "#0", ""), 2), "#")
Dim arrTemp() As Variant:  Let arrTemp() = Application.Index(Worksheets("Sheet1").Columns(6), Application.Index(arrStrTemp(), Evaluate("=row(1:" & UBound(arrStrTemp()) + 1 & ")/row(1:" & UBound(arrStrTemp()) + 1 & ")"), Evaluate("=row(1:" & UBound(arrStrTemp()) + 1 & ")")), 1)
  Let Range("T2").Resize(UBound(arrTemp(), 1), 1).Value = arrTemp()
Stop
 Range("T2").Resize(UBound(arrTemp(), 1), 1).ClearContents
' Or
Dim UnicNm As String: Let UnicNm = "aa" ' "aa"
 Let arrStrTemp() = Split(Mid(Replace("#" & Join(Application.Index(Evaluate("=IF(ISERROR(MATCH(F2:F463,C2:C463*($A$2:$A$1000=" & """" & UnicNm & """" & "),0)*($A$2:$A$1000=" & """" & UnicNm & """" & ")),ROW(F2:F463),0)"), Evaluate("=column(A:QT)"), Evaluate("=column(A:QT)/column(A:QT)")), "#"), "#0", ""), 2), "#")
 Let arrTemp() = Application.Index(Worksheets("Sheet1").Columns(6), Application.Index(arrStrTemp(), Evaluate("=row(1:" & UBound(arrStrTemp()) + 1 & ")/row(1:" & UBound(arrStrTemp()) + 1 & ")"), Evaluate("=row(1:" & UBound(arrStrTemp()) + 1 & ")")), 1)
 Let Range("T2").Resize(UBound(arrTemp(), 1), 1).Value = arrTemp()
End Sub
Sub UseNotSoInsaneFunction()
Dim arrTemp() As Variant
 Let arrTemp() = NotSoInsane("bb")
 ' Columns("T:T").ClearContents  ' Range("T2").Resize(UBound(arrTemp(), 1), 1).ClearContents
 Let Range("T2").Resize(UBound(arrTemp(), 1), 1).Value = arrTemp()
 Let Range("T2").Resize(UBound(arrTemp(), 1), 1).NumberFormat = "yyyy/mm/dd"
End Sub
Function NotSoInsane(ByVal Nme As String) As Variant
Dim arrStrTemp() As String: Let arrStrTemp() = Split(Mid(Replace("#" & Join(Application.Index(Evaluate("=IF(ISERROR(MATCH(F2:F463,C2:C463*($A$2:$A$1000=" & """" & Nme & """" & "),0)*($A$2:$A$1000=" & """" & Nme & """" & ")),ROW(F2:F463),0)"), Evaluate("=column(A:QT)"), Evaluate("=column(A:QT)/column(A:QT)")), "#"), "#0", ""), 2), "#")
Dim arrTemp() As Variant: Let arrTemp() = Application.Index(Worksheets("Sheet1").Columns(6), Application.Index(arrStrTemp(), Evaluate("=row(1:" & UBound(arrStrTemp()) + 1 & ")/row(1:" & UBound(arrStrTemp()) + 1 & ")"), Evaluate("=row(1:" & UBound(arrStrTemp()) + 1 & ")")), 1)
 Let NotSoInsane = arrTemp()
End Function
 '