I'm not sure about the threats on Tilyou. The McKane gang threatened the Tilyou family back in 1887, but you're probably thinking of something from the 1910s or 20s. If you have more info then I can try to see what I have. EDIT: I saw that he had some Black Hand letters sent to him in 1907. There were some fires on his properties later that year, but he denied the Black Hand was involved. The second fire, in Connecticut, was caused by a cigarette, same as the first fire in Coney Island.

http://www.westland.net/coneyisland/articles/steeplechase1.htm

Pelligrino Morano was the self-identified Camorra boss of the Coney Island gang. He was involved in killing Harlem boss Giosue Gallucci in 1915 and Nick Morello in 1916.
Amadeo (or Amodeo) Buonomo was the nephew of Pellegrino Morano, and he was killed on April 7, 1913, allegedly by people connected with Giosue Gallucci.

http://www.gangrule.com/biographies/pelligrino-morano

http://www.gangrule.com/biographies/john-russomano

http://www.gangrule.com/events/struggle-for-control-1914-1918