Peter Casella get 40 y for heroin traffick but made only 17 y
Matthew Madonna get in 1976 30 for h traffick plus extra 528 days in 1981 for kept his mouth shout on the drug traffick activities in NY.
John Pappa a colombo associate get life in 1997 and was in his 20s but don't flipped
George Martorano in 1984 get life for drug traffick and was 34 y old,he was released in 2015 after 30 years in the can.

There are other examples of mobster maybe young that get harsh sentences but never flipped?