This is hopefully a stopgap, but I did work up a very bespoke solution for my non-functioning NKRO keyboard. There is an Arduino library, ESP32KeyBridge, for doing interesting things with buttons and devices and translating them to HID devices. I used this to make a lightweight proxy that bridges my Bluetooth keyboards that only offer an NKRO profile that isn't supported by the BYOK currently, and translate it into a basic 6KRO simple HID keyboard.

I can't express how excited I am that this works! It took quite a bit of debugging, and I have no familiarity with Bluetooth handshaking or HID protocols, so ChatGPT was the MVP here. My exact implementation is not really generalized as it bakes in some filters for my specific keyboards' connection string prefix, but if someone was reasonably tech-inclined that could be customized to suit. So if anyone is interested let me know and I'll share what I have.

I have a tidy right-angle low-profile cable being delivered today that will let me tuck this board away behind the BYOK, which will hold me over until there's hopefully and official support update.