Sawyer & his group are locked in the Hydra cages

At the Hydra Station, Widmore's team are setting up the portable sonic fence pylons next to the cages as Seamus and the others march Sawyer's group to them. When Seamus order Sawyer into the cage, he refuses to go back in there. Sawyer takes Seamus' gun and turns the tables, but Charles Widmore shows up and fires a gun into the air, then points it at Kate (a familiar scenario resembling season 3).

Widmore informs Sawyer of something he already knows. Widmore says that he has a list of names including Ford, the Knows and Reyes, but not Austen. Sawyer gives the gun back to Seamus, who gives him a knock in the gut with said gun (flashes of Pickett).

As the group gets in the cage, Widmore tells him that they're putting him there for their own good. Widmore asks one of his men if the sonic fence is live yet and the guy says it will be another hour. Widmore says that they don't have an hour because "he's coming," he being Locke.

So how exactly does Widmore seem to have Jacob's list? While he seems very afraid of Locke, it's still unclear exactly what his motives are.