If you want to call getprivateprofilestring from another module then it needs to be a public function, however run the check outside the form
Sub LoadForm()
'Graham Mayor - https://www.gmayor.com - Last updated - 18 Dec 2018
Dim oFrm As UserForm1
Dim vList1 As Variant
Dim i As Integer
Dim m As String
    
    m = GetPrivateProfileString32("U:\test.ini", "VersionInfo", "Version")
    If m <> ThisVersion Then
        MsgBox GetPrivateProfileString32("U:\test.ini", "VersionInfo", "VersionErrorText")
        Exit Sub
    End If

    Set oFrm = New UserForm1
    vList1 = Split(GetPrivateProfileString32(IniFileName, "Indexes", "PreCompletion"), "|")
    With oFrm
        With .ListBox1
            .ColumnCount = 2
            For i = 0 To UBound(vList1)
                .AddItem
                .List(i, 0) = i + 1
                .List(i, 1) = vList1(i)
            Next i
        End With
        .Show
        'do stuff with ofrm
    End With
    Unload oFrm
    Set oFrm = Nothing
End Sub