"National IDs" for the Germain stations would be so-called RL100:
http://fahrweg.dbnetze.com/file/fahrweg-de/2394144/vHBDX5Ond...
DB has the data in systems (for instance, ETN), it's just, well, not open...
I am waiting until we translate the blogpost and our page in English before talking about that on the list. Pieter Colpaert alreday complained about uri/linked data ;)