I read over your story like you requested. To be honest, I think you need to step back and rethink some of your decisions. Right now, it's way to complicated for a story about a demonic team mascot.
You're focusing too much on facts and trying to justify the story. You don't need to do that. The audience will simply accept the existence of a monster because we do it every day- be it a serial killer or a passive aggressive co-worker.
Everyone knows that the world is a treacherous place and they are always ready to add another monster to the list. It's an evolutionary byproduct.
Do you remember when I took that job as a production assistant after graduating? Well, I spent a good part of that job sorting through paperwork for a documentary on the birth of LA. It was supposed to air on public television, but the director, Pully, ran into some health issues and it was never completed.
I remember being in the lunch room one day when Pully asked if he could sit at my table. We chatted and I ended up asking him why he chose to be a documentarian. He told me that when he was younger, he'd experienced something that he could not explain to this day:
He grew up in a suburb of Minneapolis and had a few family members who still farmed for a living. When he was old enough, he'd spend part of every summer at a relative's farm to help out with chores and such.
He had this one older uncle who was a bit of an eccentric. I guess the guy lived alone on his little farm way out in the country. The land was littered with old cars and equipment, and all other sorts of weird old things.
One day Pully's in the barn trying to find some tractor parts when he comes across an old movie projector and some canisters of old home movies. The movies were all labeled things like Christmas or Wedding, but there was one canister that simply read 'devil.' This piques his interest so he asks the uncle what's on the film, to which the uncle replies that it is indeed the devil. Then he tells Pully that he's too young to see that, but that he'd let him see it when he's old enough.
So a couple of years pass and the uncle is now quite old and unable to keep up the farm, so he decides to sell the old place and spend his remaining years in the city. That summer, Pully was sent to help sift through all the old stuff and see if there was anything that could be sold at auction.
One night after dinner, Pully gets the courage to ask about the film and the uncle agrees it's probably high time he saw the devil for what he truly is. So he sets up the old projector and the film begins.
The film opens inside an old barn. At first it's just a couple of old pick up trucks with their headlights illuminating the room. Then a crowd of men enter in a single file. They're all wearing overalls and work clothes- a pretty hard looking bunch. They file in and then this preacher walks in, dressed in a black suit. A fiddle starts up, but the fiddler isn't in the scene, though the preacher is dead center. He starts clapping his hands to the rhythm and singing this old tune:
Before the devil takes your soul
Stamp out the devil
Put the devil in a hole
Then one of the men enters the circle and shoves the young woman. The woman reels and is obviously scared to death. She tries to run, but the men prevent her from escaping. She's trapped within the circle and the stamping continues to build.
Another man enters the circle and dances a little jig that ends with him kicking the woman in the side. The group roars and the circle tightens around the woman as more and more men approach her. They push and punch and kick her to the preacher's rhythmic singing. The violence crescendos and, as quickly as it started, it abruptly stops. The whole room falls silent and the men fall into a daze as they silently file out of the room- no one saying a word. It just leaves the preacher standing against the far wall and the woman sprawled out on the floor. She spasms once or twice, but doesn't get up or appear to be conscious.
The preacher nears camera on his way out and that's when Pully notices that he's walking funny. He's got an unsteady gait and, as he nears the camera, it becomes obvious why: The preacher is still dressed in his black suit and tie, but he's not wearing shoes. Then Pully notices that not only is he not wearing shoes, he doesn't have feet, but the legs of a goat. The preacher looks deep into the camera and gives a wicked smile as he exits the scene leaving only the woman lying there- still twitching from time to time. A minute later the film runs out.
With that, Pully finished the last bit of his sandwich and told me to have a good day. There was no explanation whatsoever. I don't know if any part of that story is real or just his way of messing with the new people, but it has stuck with me to this day.
Your story needs to be more like that.