Well, as to Guard ID's. It is told that LN can go to the Omicrons HAVING GUARD ID's. Therefore, They can go to the Omicrons. However.... Omicron Kappa is a bit far. Omicron Delta is the furthest you / I can go.
Yes. They don't operate in the Omicrons, they operate in Liberty, and sometimes Rhineland or the Independent worlds between Liberty and Rhineland (Atleast I think so, this is just an educated guess). I don't see as to why they would need to deal with Nomads, that's the LSF's problem.