Why does it need to support specific cameras?
Photomatix is a 3rd party offering so without proprietary access to the RAW file, conversion/support has to be written into the program after a new RAW release (if they are written in at all). It is the same with Adobe. A new camera typically isn't supported upon release by Camera RAW. It is added post-release.
From the Photomatix site:
'If your camera model is recent, you may have to wait for a future version of Photomatix before it supports RAW files from your new camera.
The best way to check whether RAW files from your camera are supported is to try Photomatix with your RAW files. There is also a list of camera models supported by Photomatix Pro and Essentials, but it isn't exhaustive, which means that the latest Photomatix version may still support RAW files from your camera even if it is not on this list.'