I don't give it a 5 because it's not perfect.
I give it a 4 because it's great for newgrounds standards.
Backgrounds look good, that's something very lacking at most 3d animations, and you did it right. Character models look sharp, however, the rig of the faces is f'ed up.
If you don't mind, let me give you some advice, I have my share of experiences with professional 3d animating.
I know everyone have been complaining about the mouth movement. But no one actually proposed a solution, so bear with me as I give it a try.
- The facial rigging. I suppose you use blend shapes to do so? If so, try to open the mouths a little more, don't be shy about it. I see you are learning and added some jaw movement. However, the jaw movement is too subtle. As a good reference, there's the guilty gear xrd expressions that appear in the overdrives. If you're looking for a more smooth yet faster way, have a look at rwby's male characters. It's a pain in the ass to redo the blend shapes, if you already did them, but the reward is instant and it shouldn't take you too much time to lip synch. The only challenge is using those in a way that doesn't look cartoony in comparison to the short's aesthetics, find a middle point
- The stiffness: Now this I totally understand, you can't deal with 9 minutes of animation without sacrificing some movement detail. Try to add acceleration, deaccelerations and recoil to movement. Too much of a hassle? Film some coreography and use it as a reference. The trick to theese kind of low budget shorts is not to avoid expensive or time consuming animations, but to find the cheap and fast way around it.
Animation wise the best acting is from the guy at the last scene. Nice job, you're getting there.
The plot: I actually find it satisfying, it feels like its going somewhere and doesn't dissapoint. Try to focus on character defelopment. Decker smoking before shooting is actually a nice detail on character traits. Keep up the good work.
I have no experience on clothing engines like that one, but I think it works for your budget, the clipping is not that distracting.
Tremendous upgrade from the last episode, which I don't get why people complain to so much.
As always the voice acting is very good.
Cheers!