As far as I can tell, Homo Ignotus is a offshoot of humanity which, according to SCP-655, has some form of reality-bending or perception altering powers and no emotional response. Of course, no article actually explains Ignotus in-depth - the only other articles which mention them are SCP-3108, which establishes the possibility of a close similarities to humanity, and the aforementioned SCP-2003, which implies they have such extraordinary powers to effectively trigger either the extinction of humanity or an SK-Class dominance-shift scenario. I'd likely end up linking both SCP-655 and SCP-2003 somewhere in the article to give the ready some context.
Of course, what H. Ignotus can do is entirely up to headcanon and is probably one of those things that best remains as a mystery, hence the throwaway document.
As for the historical logs and recent encounters, I see the potential issues, but I'm hoping that if and when this ever makes it to a draft phase I work it out so they don't come out as cliche- the redactions right now are more so there because I haven't given too much thought to this at the moment.
The 'core' anomaly would be the Ignotus population specifically on the island - the island itself, if I ever decide to make it anomalous, would be a sub-designation. I want to believe Ignotus is more than just "anomalous magical peoples" but that could become a major issue - might be the reason why there hasn't ever been an SCP dedicated specifically to Ignotus yet.
Thanks for the feedback, Zyn!