Leo shouldn't be reckless. Right after that phone call with Randall, he texted the Cassanos back that he's going to finish the plans alone. There's no need to follow him through, or even intrude to his intentions. On the other hand, Randall slammed his fist on the table, knowing that a careless Leo would bring nightmares.
Along with the three members of the warehouse's protest team joined him with several weapons, Leo made sure that no one can betray him. To be certain, he briefed everyone earlier about the consequences of what they're going to do. Now that he's down the drain and Zella's gone from the mansion, his habit has come back again.
Killing was detrimental. Everything was such heinous that a soft person's cause of death would be murderers. Lots of blood pooling in the floor, and the cracks were showing up in the skulls. Bullets hit arteries, exploding them into a severed tie.