I'm not sure about Accardo's mental state, but he certainly was in very poor physical shape. My opinion is that Accardo didn't give a flip how these guys were killed. He was a cold-blooded killer just like most of the other Outfit members. He was sending a message and making a point.

Accardo had no personal involvement (IMO) in these murders. He was probably 3-4 X out of the decision ( he told someone who told someone, etc.) Again, well insulated by some of the most hard-core Outfit men. Yes, the true colors come out and people die. This is how OC works.