This whole thing sounds like scam. I don't think this keyboard is possible to make at $199. Every piece of eink display under the cap costs a few bucks. Then you need insane custom switching board to multiplex all these displays with SPI lines. Probably needs an FPGA to do it fast and reliably. The raw BOM cost alone will be $100 or more.
Fabbing a custom size eink display will cost $200K in tooling + R&D if only they could find a fab that is willing to do sub 100k MOQ orders. Otherwise, it is upwards of $500k. The thing is, no other customer will ever buy a 12x12mm eink display since it is too small to do anything useful, so the eink display manf cannot ammortize the cost of a new line spin up and tooling. It has to be captured and it will be costly.
Fabbing a custom size eink display will cost $200K in tooling + R&D if only they could find a fab that is willing to do sub 100k MOQ orders. Otherwise, it is upwards of $500k. The thing is, no other customer will ever buy a 12x12mm eink display since it is too small to do anything useful, so the eink display manf cannot ammortize the cost of a new line spin up and tooling. It has to be captured and it will be costly.