Lucky you did do more damage... I'd look at your pulleys and idler bearing(s) very closely then, replace the belt and pulleys as needed. That spring bouncing around in there may have marked/damaged other things the belt rides on.
I honestly think its pointless. I didnt put one back on this morning when i fixed it. It doesnt seem like it serves no purpose. anyone know anything i could do with this little thing ? Lol