In your cost analysis, did you consider the price of decommissioning each plant in the future? That's running at about 3 billion per plant in the UK at the moment?
https://www.theguardian.com/environment/2022/may/20/uk-nuclear-power-stations-decommissioning-cost

Additionally, did you consider that as the world gets hotter, there will be more problems with cooling the reactors? In France they had to radically reduce the power output during the heatwaves last year which made the river water temperature too high:

https://www.theguardian.com/business/2022/aug/03/edf-to-reduce-nuclear-power-output-as-french-river-temperatures-rise

Does your cost analysis take into consideration the lifetime storage cost of the spent fuel? The UK government disclosed a projected 11 billion cost of Geological Disposal Facility (GDF) for our current infrastructure plans. Apparently the cost of disposal mangement can be almost as much as the operational cost of the plant itself.

And one final thought. There has been about 600 plants operating around the world, which has resulted in two catastrophic events. The cost to mitigate Fukushima is estimated to have been about 200 billion dollars. So if history repeats, and 1 in 300 reactors experience some critical event in their life times, then that adds another 600 million in cost per plant.

I wouldn't be surprised if the end to end cost per plant is a good 5-6 billion more expensive than you're calculating at the moment.