The CKRA, at least for this market, was the last gasp of the "old" engine family (dating back to 1998). The only other engine currently sold here from that family is the gas 2.0L engine in the Jetta S, which is sadly slated to go away after the 2015 model year.
That said, the CKRA is quite a bit different than the other CR diesels within that family, the CBEA and CJAA. It shares hardly any parts with the others in fact. It is quite unique, really.
The new family of engines, while not a radical departure from the basic layout, is very different yet, and while the 2015+ Passat still does get a unique engine code, it isn't really all that different from the 2015+ Golf, Jetta, A3, and Beetle.
Keep in mind, we only see a small fraction of the engines that VAG produces for various markets around the world. It is likely the CKRA is not all that unique in Europe, as it may share a lot of components with other engine codes sold there.