Pretty sure he killed the guy too, what a beatdown that was.
Considering that he threw a large chunk of cash at his corpse and said something to the effect of, "that'll pay for his funeral," yeah, I think he killed the guy, too.
Great escalation in this episode with the gas station shooting. If I'm not mistaken, Rothstein actually owned the product so it looks like Rosetti has made New York an enemy - not a wise choice.
The way they're developing it, Rosetti is in the clear from Rothstein. Rothstein is paying for the product to arrive, and Rosetti is purely Nucky's problem. Until the product is in Rothstein's hands, Rosetti isn't stealing from him whatsoever.
At least, again, that's what they're saying in the show.