Unable to link and autofill upto last cell from another workbook

Sub CopyDataCB()
'
' CopyData Macro
'

'
    'determine Last Row
    Dim LastRow As Variant
    Dim SourcePath As String
    SourcePath = "C:\Users\smalghan\Desktop\q11070\01_Working\Quantities_StormCAD.xlsx"
    Workbooks.Open (SourcePath)
    Worksheets("Catch Basin").Activate
    LastRow = ActiveSheet.Cells(ActiveSheet.Rows.Count, "A").End(xlUp).Address
    MsgBox "LastRow: " & LastRow
    
       
    'Determine last cell
    Dim LastCell As String
    LastCell = Range("A1").SpecialCells(xlCellTypeLastCell).Address
    MsgBox "LastCell:" & LastCell
    
    ActiveWorkbook.Close
        
    Worksheets("Catch Basin").Activate
    Range("A1").Select
    ActiveCell.FormulaR1C1 = "='C:\Users\smalghan\Desktop\q11070\01_Working\[Quantities_StormCAD.xlsx]Catch basin'!RC"
    Selection.AutoFill Destination:=Range("A1:LastRow"), Type:=xlFillDefault
   
End Sub