Personally, I haven't ever attempted to take this approach. Have you tried putting it inside the double quotes right after "iTunesRemoteControlDaemon"? Give it a shot.
If it doesn't work, you might want to ask if you actually reboot your system enough to merit going through the trouble of auto-starting this.
If you want to proceed, I'd question why you're using AppleScript to simply run a shell script. You don't need this extra layer of scripting. Your shell script doesn't need to run as admin either. It just needs to run as your user account.
The link I posted before that references login hooks on bombich.com should have been a pointer in the right direction. You ultimately want to have this thing start up as a normal daemon process just like lots of the other things that start up, right?
If you just want a double clickable item to run the script for the dock, you can do that by researching some more on Terminal and saving a terminal session as a Term file. In fact, there a long series here on macdevcenter about that.