Well PG&E said they'd take care of everything if it was in fact their problem (i.e. not someone planting fireworks near a gas line or something), however the fact people apparently smelled gas for weeks before, as well all these other issues about similar problems coming from elsewhere in the past, it looks to be pretty obvious this is their fault.
Assuming they have insurance though absolutely go through them, and they'll be the ones going after PG&E making the job a bit more easier on the homeowner. I can only imagine the emotional aspect of it, hell they may not even want to live in the same area any more and might want to simply buy a new home with any settlement. It was a nice area, who knows how long it will take for the whole area to be nice again, not to mention if she even wants to live in that area any more.
I'm sure she'll be fine though, hopefully she didn't have too many memories that burned up there.