I had a clicky noise that would go away when I reset the tensioner (retract and release the tensioner bolt) but it would come back. I replaced it but damaged the threads for the cap bolt when tightening. I used some high-temp RTV sealant to glue a small coin over it.
Yours is damaged in a different way. The aluminum threads came out cleanly when I tightened mine too much where yours seems to have cracked somehow… perhaps when someone tried to insert a screwdriver to retract the tensioner bolt.