I finally used these lines of code
Arg = "'" & Path & "[" & File & "]" & Sheet & "'!" & "R4C4" 'Range(Ref.Range("A1").Address(, , xlR1C1))C
'Execute XLM macro
GetValue = ExecuteExcel4Macro(Arg)
Way more simple with some loops.
solved get value/charts in another workbooks without opening it