I agree 100%. I've commented a bit on this previously but I wanted to add a bit more since then about why I feel like the bangs are gunshots.
I work in a construction facility where we have an abundance of loud tools and machinery; nail guns are one of the loudest we use. Hammers are a necessity for nearly every worker as well. We carry many different brands of both as we run through them very quickly so they're always being replaced.
I'm literally listening to a nail gun as I'm writing this out. When you stand nearby a nail gun while it's used, it's quite loud and you hear a definite bang as the nail enters the material. However, as soon as you have a door or distance between you and the nail gun, the most audible part of the bang is gone. It's almost as if the material is removed and only the operation sound of the nail gun is heard. I can't explain why this is, but if a nail gun was fired inside the home, I think it would more likely sound like an "airy thunk" rather than a bang on the audio. As for hammers, I have never heard a hammer come close to the same sound volume made by a nail gun, no matter what material it was being used on.
I am very obviously speculating here and could easily be proven wrong. There are way too many factors to be remotely certain unless a person had inside knowledge, which I definitely don't have. And there could be factors at play in my facility that make the sound carry different than it does in the video.
It's very possible that a hammer was used to make a hole in the wall so I'm not trying to disprove that theory. Maybe a person made the hole with a hammer, realized they still couldn't gain entry into the room and instead decided a gun would be better which was the part picked up on the audio? I have no idea. It's still possible it wasn't a gun at all and I'm wrong.
Is it not also possible that the hole was made to hide evidence of a stray bullet. Easier to explain a fist than a stray bullet? Who knows?
But, again, I'm just speculating. Wish I knew more so I could stop speculating and have real answers. MOO