If this is indeed an excel mistake (which I strongly suspect), I wonder if it is one of the more expensive ones.
If it was indeed a spirit-medium con (who could say otherwise), I wonder if it is one for the ages.
If it was indeed a Feng Shui conflict (many might say it was), I wonder if it is one of the more consequential ones.
I'd love to know more.
It sounds like they were using an ARR model that failed to take into account partial usage, in a significant way.