General Abbott shoots down a seaplane with an RPG. This is next to impossible as an RPG is a line of sight weapon. It has no guidance or homing package. To hit a plane, unless it was parked on a runway would be nearly impossible.
Gus has only three points per antler, and one of his antlers was taken just above the bottom point. However, when Dr. Singh picks up Gus' removed antler, there are three points on it when there should only be two.