The 2 other's that Senter named that were with him the night he shot Gambino were Richard Chaisson and Warren Schurman, Senter is actually the Uncle of Anthony and was a Gambino associate at the time I think.
The reason I think that James was killed is because I think it was his idea to start this kidnapping ring and he was the main name they were hearing could be the reason why.
If it was me I would have wiped them all out.
Why not just give the contract to The Arm?