She claims that it's a tail light issue, but from what i've been reading, that's not the case. According to 2005 toyota manuals, prius, it says that if parking brakes are on and the lights are still on, then take it to the toyota dealer. Is she just trying to dump the problem on to an unsuspecting buyer? Here is the inserted picture I use:
i can see the pic. i think you need a code reader. if dealer told her it's a tail light issue, call them and ask what codes they got. i don't think tail lights set trouble lights