Need Extendscript assistance

I have just tried with the system command and that failed for some reason so tried a batch file and that worked fine, mine were cr2 file but have changed the extension to suit...

#target photoshop
function main(){
var DNG = decodeURI(app.path.parent.fsName)+"\\Adobe DNG Converter.exe";
var inputFolder = Folder.selectDialog("Please select the folder with Files to process"); 
if(inputFolder == null) return;
var fileList=[];
fileList = inputFolder.getFiles("*.rw2");
if(!fileList.length) return;
var DNGbat=File("~/desktop/DNGbat.bat");
DNGbat.open("w")
DNGbat.writeln("@echo off");
for (var z in fileList){
 var command ='"'+DNG+ '" -c "'+decodeURI(fileList.fsName) +'"';   
 command = command.replace(/\\/g,'/');
DNGbat.writeln(command);
    }
DNGbat.writeln("cls");
DNGbat.close();
DNGbat.execute();
}
main();