Cuz the is still a "Secret Achievement" here the Infos:
Wanted: Dead or Alive - Captured Al Bashir
Operation Nightshift
You get this Achievement at the End of the Mission Nightshift and u cant miss this, if you complete the Mission. You simply need to shoot the escaping Car with Al Bashir inside.
(Video is recored with the German Version, playing on Hard and no HD-Texture Pack installed)