Ref: Vito's slipup [Thanks Turnbull for the link]
Wow! so many threads! There isn't enough time!

Both Vito's consiglieri Tom and Vito's underboss Santino were “totally in the dark” had no idea Vito had sent Luca to Tattaglias thus to Luca's death

Spot on! “And Vito handed Luca, Vito's one-man murder machine to Sollozzo on a silver platter:”