You do not understand the bug. The bug is that classes who should have 2 weapons showing up both on different sides of the body in cutscenes now have the offhand on opposite side of the body since the release of 4.0, with no main hand weapon present.
This is what it looks like http://imgur.com/a/vJzt6
Two-Finger's Revenge (an offhand only blaster) is where the main hand should be, and the main hand weapon is nowhere to be seen. If a character draws a weapon my actual MH weapon magically appears in my hand and the OH is still holstered on the wrong side of the body.