Megan....please don't hesitate from asking questions. This is the place to do so.
At one point "maximum benefit" will occur with your Mom's current treatment. In either case, ineffective or maximum benefit, the molecular testing results of Foundation One's analyses will will identify DNA alterations (faults) for which a targeted drug may be available or a clinical research study is conducted. Or, perhaps some type of radiation treatment may be applicable. In any case, you are ahead of the game and that is very good.
It is likely that UCSD is the place you ultimately choose, but a second opinion is of enormous value.
The real value of this forum lays in the information passed on by patients and caregivers, hence I hope for others to chime in.
In the meantime, dear Megan, try to relax. Your Mom has been diagnosed, she began treatment and much, much more has yet to be determined.
Oh, and thanks for removing the links. I too have to do this occasionally for my postings as well.
Hang in there,