Firemen, paramedics and other rescue workers have the same concerns about airbags and will sometimes disconnect the battery before trying to extract someone if the airbags haven't already deployed. There have been some deaths of rescue workers from airbags deploying after an accident. I don't think any cars have automatic disconnect sensors for them.

The chances of all the battery disconnect sensors all going bad is pretty slight because there are so many of them. The main battery can also be disconnected directly. In addition, all high voltage cables are thick, identified and orange in color.

I had some damage to my Prius and it also took around three weeks for the repair. They didn't need to have someone come to disconnect the battery though, they just looked at my owners manual.

Why 3 weeks... Prius are very popular and it took time for the parts to come in... one of the drawbacks of such a popular car.