She doesn't have to come to SF for FP. FPs are sent to FBI
electronically via networks, and INS gets the results only from
FBI, ignoring where they are taken.
Our application was submitted from bay area, and for the
similar reason as yours, one of us had our fingerprints taken
in Florida. And it was fine.
Also, it was told by INS officer that it is acceptable to take
FP at a location other than the one assigned by INS.