I believe for an explosion to occur there are some conditions - Rapid expansion of volume in a confined space, for one. Unless the fuel that was actually inside the tank was ignited, not just the spilled stuff on the surface of the car and floor, it should just burn away.
I wouldn't get out and approach her though because in her panic though she was still pumping fuel from the nozzle, spraying fuel and subsquently spreading flames around like a mock flame thrower. Might end up getting covered in some of it and burned.