Furio, there are many more than just those guys you´ve listed.
There is a post in here, in a thread, with a list of compiled Mafia turncoats already done by Ivy.

And while we´re on the subject, Joe Valachi was not the first turncoat in US Mafia history.
In the early 1920s (if memory serves me right), Ralph Daniello´s corraboration with police helped solve several murders.
Daniello was a member of a Camorra gang in Brooklyn though (not a Mafia member).
And also in the early 1920s, Bartolomeo Fontano blew the whistle on a gang dubbed (by the media at the time) "The Good Killers". This gang seems to have been part of the early Bonanno Family and included mafiosi Stefano Magaddino (later boss in Buffalo), Bartolomeo DiGregorio, Mariano Galante, Vito Bonventre, Giuseppe Lombardi and Francesco Puma.