The guys from NFCworld found the ams chip now: http://www.ams.com/eng/Products/NFC-HF-R...
Seems you cannot find it Googling for it.
From the block diagram it seems the AS3923 is connecting to the antenna not the NFC controller.
Fits to the description saying that the chip is replacing the drivers of the controller.
They also mention to support peer to peer and other modes so we can hope for more than just payment it seems ;) Cant wait to get one...
Did you teardown the keyboard too? Whats used for backlight there?