Thanks a lot! I've seen the Copterline S-76 accident report and that is exatly what I meant for the second type. There is also another accident report I can find today is the Eurocopter AS350-B2 helicopter accident. In that accident, the servo control input rod got disconnected from the input lever because of bolt failure. But I'm not sure whether this kind of failure would lead to a locked-in-position of the servo.
As a result, maybe the stuck failure is rather rare compared to the first failure type.