If you turn on the controller setting where it swaps left and right trigger/bumpers, the left trigger still does boost while the right doesn’t do anything. And there is no button to make the ghost shoot. This problem is in Halo 4 but I think the setting works fine in Halo CE
If I hijack a ghost and start holding left trigger during the animation then the ghost will shoot.
This problem also exists in Halo 2.