Okay, took a look at this. Here are my thoughts:
Right from the start, the containment definitely needs work. The "keycard" system from the (unaffiliated) SCP games is actually a pretty bad system, since keycards are very easily misplaced or stolen. It makes sense in-game so players can get into areas, but from an in-universe standpoint it's a huge security liability. It would make more sense to just mention that access is restricted to Level-3 personnel (not "personnel level 3") and not say anything about a keycard. The organization of the containment is also pretty shaky, since you mention the physical thing (standard storage vault), then jump to personnel observation, then back to physical containment (the elevated table) again. Ideally, the containment should flow smoothly from one topic to the next. Make more than one paragraph. Also, given how easy it is to keep this thing contained, it's definitely not Euclid. Also, refer to SCP objects as "SCP objects", not "the SCP", which in-universe refers to the containment procedures, not the actual thing in containment.
And on and on. Pretty much every sentence in the draft could use some tweaking to make more sense in a professional clinical setting. You have a lot of unnecessary "fluff text" that can be shortened or just trimmed out. For example, the description takes several paragraphs to actually mention the primary anomaly. You also have a lot of overly casual phrasing, like "creatures begin appearing out of nowhere, attacking the player and attempting to kill them."
Most successful SCP authors have at least some college-level writing experience, since clinical tone is typically covered in college. If you haven’t encountered clinical tone or writing analytical essays in school yet, it can be hard to write an article that possesses the unique "flash fiction as written by a professional scientist" tone the site audience is looking for. If you tell us where you are academically, we can recommend some materials you can study up on, such as these college resources for clinical tone:
http://www.aje.com/en/arc/editing-tip-maintaining-formal-tone-scientific-writing/
http://academicguides.waldenu.edu/writingcenter/scholarlyvoice/tone
https://healthcare.utah.edu/brand-and-style-guide/writing-guide.php
Anomalous video games that make things real aren't new by any means, so this should have definitely gone through the Ideas and Brainstorming forum before you started writing a draft, since the current portrayal isn't unique or unpredictable enough to stand up with the existing works with a similar premise. That combined with all the basic writing errors (another thing: the censoring is a little sloppy—I recommend reading over this guide on interesting expungment for some tips on when to redact information meaningfully) makes it very unlikely that this will do well on the site without some serious overhaul.
Why does this need to be checked once a week, or watched for changes in appearance? Nothing in the description seems to merit these procedures. Why can't it just be kept in a locker?
"Handheld portable video-gaming device" seems redundant, cutting out "portable" here would probably be fine. Not sure what it means for this to be "in a permanent sleep mode" since you then go on to describe what sounds to me like the normal process of turning a device on and off, by use of the power switch. The focus on the length of time the loading screen may take seems to suggest that this detail could be important, perhaps related to some feature of the player, or having some effect on the game that follows, but this is not addressed further, making this seem like an irrelevant detail.
I'm bothered by the [DATA EXPUNGED] fate of the player because it seems to me to be used as a general "a fate worse than death" substitute. When the object ultimately ends up as a thing that kills you, in a pretty clear way, it's not giving any indication that something more interesting could be behind this expungement.
When you say "sightings of SCP-3572a are possible, but only by watching over the player's shoulder as they play SCP-3572", is this referring to images on the game console screen, or the monsters present in the "real world," so to speak? Are people who observe a player affected in any way?
Some casual language in the description of the creatures could be excused by the fact that they can't be properly observed or measured, but "they boast long arms and legs" could be more clinical (particularly the word "boast"), especially if researchers are able to see at least the renderings of the creatures in game. In "long claws and teeth seem to be their preferred method of execution," I think that the claws and teeth are the means, but not the method, which would presumably be a more specific use of those means, such as evisceration or exsanguination by biting or clawing. The word "execution," has connotations of intelligence and planning that I'm not sure make it the best choice, unless these monsters are shown to act in a way that suggests something more than animal intelligence.