Tried to find some testimony from Lawrence Iorizzo, who was Franzese's partner in the gas tax scam, to see what he had to say about the guy. Came across these:
https://www.researchgate.net/publication/225876645_Organized_cross-atlantic_crime

https://www.vanityfair.com/news/1991/02/john-gotti-joe-columbo-fbi-investigation-witness

Even though it's the word of another rat, they show a different side of Franzese. More shady and prone to violence than he likes to let on.