Taking a quick glance at your post history, it appears that you do not have an I&B thread for this idea. For future reference, that forum (which is where I usually hang out) is where users will go when they have an idea for an SCP and would like help in developing said idea, as well as analyzing it to see if it would even be workable as an SCP object, tale, or GoI Format.
Unfortunately, you would have saved a lot of writing if you had gone over there with a decent spread of what you had wanted to accomplish. I'm a dude who likes interesting articles, long or short, but I found this to be quite the slog.
First, you lack a clear focus. You have a ritual that opens any lock as the primary anomaly. This has already been done, as SCP-005 is a literal skeleton key. In this respect, you are correct in assuming that this is not enough to carry your idea. That is, I presume, why the labyrinth came into being. While it does add room for story and character development, it does not do so in a unique way (as there are already a handful of labyrinth articles, most of which also have monsters in them), nor does it do so in an interesting way. By the end of the first expedition, I just wanted the article to be over already.
Second, there are just so many anomalies here that you require a concise and simple naming system, yet you do not have one. If you ask me, I would make it so the ritual is SCP-XXXX, the Labyrinth is SCP-XXXX-1, the guide is SCP-XXXX-2, and SCP-XXXX-3 are the other creatures (the jellyfish, the poison guy, etc.).
Third, your characters are very bland and lifeless. Both D-class come off as cartoonish, and the second D-class who is lost at the end feels very much like a Mary Sue, and I hardly ever use that terminology. I mean hell, the fucking O5 council mourn her loss at the end. It doesn't get much more Mary Sueish than that if you ask me. In addition, your agent is a bumbling idiot who can't lets D-class steal his gun, trigger explosives, and just generally boss him around, and he comes off as a bland foil that your D-class hero character exploits so they can save the day.
Fourth, after all that slog, all those exploration logs and interviews, there is no payoff. You slapped an O5 note on there that basically says "Fuck you, this is done. Stop asking about it because testing is over. Hope you weren't invested in the story or anything."
Lastly, there are serious tonal breaches and minor SPAG errors all over the place. Sites like Grammarly and essays like Clinical Tone Declassified and Clinical vs Complex help explain how to fix this.
