Would you like to run the same calculations for the (now decomissioned) nuclear power plant on the same site?
Or for that matter the average petrol or natural gas storage facility? https://en.wikipedia.org/wiki/Buncefield_fire ("Europe's largest peacetime explosion")
A nuclear power plant cannot free all of its energy at once as the fuel enrichment is too low for an exponential excursion of power, i.e. an explosion.