In the finale of Season 3 of Person of Interest, it was revealed to Team Machine and to the audience that Decima Technologies was behind Vigilance, and that they planned the bombing in the courtroom. In particular, the bombing resulted in Samaritan receiving NSA feeds and being fully activated.
Later, in Season 4 Episode 12, Team Machine had kidnapped Control and wanted to convince her how bad Samaritan is.
Why didn't they mention the connection between Decima and Vigilance to Control?