Ok, ok
So we would have to accept that one engine would starve if you had to use all the fuel on board when you still had fuel. Not a good situation.
So I would manage it like I said: a revised minimum diversion fuel and end of the story.
I don't think you can develop too large an imbalance in that scenario anyway, but it could happen (being very unlucky) that you needed all of your fuel that very same day.