Scarfo and Manna became close in the early 70's in Yardville, so they were tight long before Bruno got whacked. In fact in Phil's book he mentions going to Manna's restaurant with Scarfo and Manna basically let him know Bruno didn't have long to live and Scarfo said he was fine with that, so even though he wasn't directly involved he wasn't gonna save Bruno either. I doubt this was the case with Phil Testa though.

I've also read that Nick's father was connected with the Genovese but that seems up for debate, it would definitely make sense though.

As for your point about Chickie, in Phil's book he mentions that nobody on the street knew that Chickie Narducci was involved in the Testa murder plot except for Nick, because he found out from the West Side administration, who found out from Pete Casella himself. I can see them leaving that up to Nick to handle as he saw fit rather than putting their own guys at risk.

I'm sure Serp can offer better insight to all this, just things I recall from reading.