[You may be right from a legal standpoint, but logically it still doesn't make sense to me--unless Michael said something like "Do whatever it takes, I don't care what" beforehand.
I believe that something like that happened in the case of the hooker:
I've always held that Michael would never have given Tom a blank check to have a US Senator implicated in a murder, even though he told Tom, "You're gonna be the Don." Geary was a regular at Fredo's brothel--and with that hooker ("...we done it be-FOE-wer..."). Either Fredo or the manager (the guy who looks like Gene Vincent) would have noted that, and would have gotten that info to Michael. He would have regarded it as gold. So, after the "oily hair/silk suit" rap, Michael probably turned to Tom and Neri and said, "Nail his ass the next time he shows up at that brothel."
