If she applies again wouldn't they give her a hard time because of this issue? There has to be a way for her to solve this with the appeal or an attorney before she applies again and pays the fee when she might be able to get it resolved.
Since claiming to be US citizen is deportable, it can only be resolved by
judge's cancel of removal decision, re-adjustment of status to PR etc. Otherwise it is always subject to USCIS prosecutorial discretion.
Their decision not to deport the offender this time does not mean
they can not deport the p[erson next time unless the above process
kick in to resolve it.
But the OP's girlfriend has no choice now. To get a cancel
of removal one need to be in removal in teh first place, and to get there,
one should start citizenship application again with perhaps better results
--just approved!!!!
So the OP's girlfriend has the following options
(1) appeal the denied application. I believe this is very hard because the wroingdoing occurred within 5 years
(2) Forget about citizenship and make peace with reality of just living in USA as PR for the rest of life - the cons of this option is that
one such thing occur, one is fully aware that GC only carry a risk and one always can run into trouble due to ignorance etc
to get deported
(3) Reapply for citizenship after oct 2009 with possible outcomes as
(3.1) approved,
(3.2) denied but with USCIS decision not to deport her
(3.3) denied but with USCIS decision to deport her
If (3.1), everything ends well, if (3.2), then it is back to what the situtation is today , if(3.3),
then you choose to fight the removal without certainty of wining or leave teh country