I've noticed on the Big Book of Amiga Hardware site, that CDTV keyboard came in 2 versions, one with black caps, one with grey ones. Which one came first and with which model of CDTV?
The Commodore CDTV did not come with any keyboard, mouse, or external floppy drive. These accessories were available by purchasing the optional "Expansion Pack" for ~$200.
To my knowledge, all the accessories in the Expansion Pack were fully and completely black. The keyboard was identical to the contemporary keyboard that shipped with the A3000, other than being all black.
While I'm open to the possibility that there were some early version keyboards that did not have black key caps, it seems a simpler explanation that over the years various other model Amiga keyboard parts have been repurposed. Also, I am only aware of a single Commodore product code for the CDTV keyboard (CD 1221).
There were grey versions, particularly in Germany. It was not marketed under a different model number afaik.
For images see https://bigbookofamigahardware.com/bboah/product.aspx?id=661