Yes, Buscetta is both bodyguard and assassin.
Certainly Michael knew that Roth was behind the Tahoe attack (as he told Pentangeli). Buscetta was set to kill Roth after he whacked Johnny Ola, but Roth's stroke intervened.
Ntra la porta tua lu sangu � sparsu,
E nun me mporta si ce muoru accisu...
E s'iddu muoru e vaju mparadisu
Si nun ce truovo a ttia, mancu ce trasu.
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