I spoke with Kin and TrueCustom earlier in the year and they had mentioned that the group is no longer together. The owner of KBDMOD who used to sell them is no longer in the kb business.
On Korean keyboard forums NOTHING is permanent or produced all the time because then it would be another Filco, Leopold and Ducky Corporate Structure.
That is why when a unique Korean Custom is designed and made, it will always have a far limited appeal and access to even their own citizens let alone foreigners in other countries. Plus Koreans are more isolated than the Japanese when it comes to keyboard adoration and support.
Suspect they love keeping the access down to a minimum, which helps keep certain models highly desirable due to their own rarity.