Porting feedback over:
is referencing another SCP not allowed?
It's allowed, but not necessarily recommended.
I personally thought that was interesting, but if thats not allowed or considered instantly cliche, I will drop.
The usage here doesn't particularly benefit either this article or SCP-008, mainly because you could effectively swap out 008 for a number of other contagion/medical SCP articles and the narrative wouldn't change much. As such, it's kind of like unnecessary padding fluff text to just have someone say "oh yeah, also we want to check it for this other anomaly".
The humanoid may be dangerous, but I don't know whats stereotypical about it.
I paid attention to the humanoid writing guidelines, and it's not about containing a dangerous humanoid but experimenting with its anomalous properties.
Yeah—you focus way too much on its behaviors and anomalous properties and it kind of comes off as a D&D stats sheet or video game boss description. The backstory of "there's a serial killer involved, also the Deathstalker scorpion for some reason" doesn't really divert from those sorts of rule-of-cool themes, as well as the overall kind of creepypasta feel that the site has migrated away from in the 8-10+ years since it was first started.
I personally also disagree with most of the experimentation—the whole "Necessary testing with various D CLASS personnel is required to establish aggression levels and attack methods employed by SCP-3353." bit doesn't really seem necessary to me. The Foundation probably doesn't really need to know every attack pattern that this thing has at the cost of plenty of hard-to-replace trained/orientation-completed D-Class.
Overall, it feels like something that might have done okay 8+ years ago when that sort of thing was more commonly-liked, but after that many years of seeing those sorts of things be posted, and lately fail in recent times, it's just gotten kind of stale.