"the gentle don" from Philly.

That would be Angelo Bruno.

Paul C had become a weak boss and naively trusted Gotti

He certainly didn't "naively trust" Gotti. Rather the opposite. He seems to have considered Gotti never as more than a thug, and in his final years their relations were rather strained; Gotti was more or less safe as long as the respected longtime Gambino underboss Neil Dellacroce was still alive and protecting him (and as can be heard on a wiretap, Dellacroce was getting impatient with Gotti and Gotti's friend Angelo Ruggiero at the end). Once Dellacroce was dead, Gotti knew he would be at least demoted from (acting) captain to soldier (with the accompanying loss of income, not unimportant considering Gotti's gambling habit), and probably even be killed.

But Castellano made a big mistake by replacing the powerful Dellacroce with the nonentity Thomas Bilotti and not appearing at Dellacroce's funeral. Of those not directly involved in the conspiracy against Castellano, most did not care anymore if Castellano was killed. The few exceptions (such as Castellano's nephew Tommy Gambino) would not start an internal war.

He was called the teflon don after all.

In the 1970s he got away with a couple of years (or so) for the killing of James McBratney because his lawyer was none other than the infamous Roy Cohn. In the 1980s, he got away because jury members were bribed (it was Gravano who took care of that).

RICO legislation was enacted in the early 1970s, but it was only in the 1980s that DAs started to actually use it; the Commission Case in the mid-1980s was the first real test of the RICO act; it lead to the incarceration of the administration of 3 of the 5 NYC families (the Bonannos were not on the Commission at the time).

I will look for the CP angle you mentioned

Page 111-112 of the paperback edition of Murder Machine. It's based on Dominick Montiglio's testimony. Demeo's arguments ("My business is just buying and selling", "there's a lot of money in this") sound fairly typical for Demeo (his son reports that his father was constantly on the lookout for new ways of legally or illegally making money). But it seems that at the time he had not yet learned that you don't always need to tell your captain where that money you kick up to him actually comes from.