It was never said that the safety of the flight was jeopardised in any way as long as you have the other means of power.
In the scenario given its a normal flight, but with a bat discharging.
Fact of the matter is the Hot battery bus and switched hot battery bus will eventually be zero after 60 mins (dual battery), and the fire protection uses it.
And if my understanding is correct of the electrical schematic, nothing else powers it except the battery.
With that in mind, and also the fact it will be a no go once landed, i will be on to maintrol to discuss what they're thoughts on it seeing as they are engineers and know more than me.