You need to tell the run to wait until the process is finished. Something like:
const DontWaitUntilFinished = false, ShowWindow = 1, DontShowWindow = 0, WaitUntilFinished = true
set oShell = WScript.CreateObject("WScript.Shell")
command = "cmd /c C:\windows\system32\wscript.exe <path>\myScript.vbs " & args
oShell.Run command, DontShowWindow, WaitUntilFinished
In the script itself, start Excel like so. While debugging start visible:
File = "c:\test\myfile.xls"
oShell.run """C:\Program Files\Microsoft Office\Office14\EXCEL.EXE"" " & File, 1, true