Yeah I am familiar with the E. Moneybags story, and definitely heard that speculation L's murder before...seems plausible to me. Would not be the first or the last accidental hit.
I don't know though, something about the whole Frank Matthews story seems overall legit to me. He bought a house in Todt Hill, which was almost exclusively for the Italian Mafia...like a crazy nice house for that period in time. And not only was it in a Mafia hub, but he was literally the only black family living in that area at all. And the thing that really makes it believable to me is all the interviews they had with the police who were running the investigation...Multiple jurisdictions, different agencies...and by the fact that they never caught the dude (and 40 years later seemingly never will) you'd think they would downplay it if anything, just so they don't look bad. But these cops are very specific about the amount of money he was dealing with. They had a hotel mic'd up at one point and they got proof that he pulled out $5 million cash on some South American dealers and as a joke was like "let's see if you can match that..." - Anyone dealing with that amount of cash in those days definitely seems feasible that he was able to get out the country with $30 mill.
The other interesting part is the CIA made the police drop any South American aspects of their investigation because they were encroaching on The French Connection, and others who the CIA were working with in regards to certain black operations involving Cuba & the Russians in the late 60's early 70's. So for a large part most of his story is corroborated.
But overall I hear you, and agree with you. Most of this shit is embellished to some degree. I just personally believe that numbers wise Matthews has to be up there in terms of highest earners in that time period, or even overall if we are adjusting for inflation.