Illustrator Scripting :: How To Add PDF On Top Of Existing PDF

Im trying to add a pdf on top of an existing PDF in illustrator using a script. This is supposed to be done by anyone at my firm so that is why I want it in a script. I also have a lot of other functions that works that will do some other stuff with this document.
 
Created this from the scripting guide but it doesnt work. Im pretty sure its the embedDoc var thats empty and i dont understand why. Im not sure if the File "points" to the directory of the script or the original file but Ive tried both ofcoarse.
 
This is the masterpiece
 
var embedDoc = new File("/temp/testfile1.pdf");
if ( app.documents.length > 0 && embedDoc.exists ) {
var doc = app.activeDocument;
var placed = doc.groupItems.createFromFile( embedDoc );
}else {alert("suck")}