"SP People" appears to based in Korea.
I would guess they're just a group of designers.
It is likely due to their non English speaking background, that they're not that familiar with Geekhack forums/culture, which might explain why their KAT Lala IC was submitted with less than a week leading into Groupbuy date. After all other non-western enthusiasts in countries like Korea, China and Vietnam have their own forums/ICs, which is why you'll see custom keyboards in the wild that never had a post on GH.
3ditda seems to be SP People's e-commerce site:
https://www.3ditda.com/blogPost/kat_cats_eye The fact that their name is similar SP (Signature Plastics) who manufacture SA profile keycaps is purely coincidence.