That will tell you that you shouldn’t expect to spend more to save one life than estimated from the top charity; it might even tell you that the expected cost of the top rated charity is higher than the estimated cost from the next-ranked charity.
Without a reason to believe that the accuracy of the estimate for the lower-ranked charity is greater, you can’t conclude that the expected cost of the higher-ranked charity is greater than the expected cost of the lower-ranked charity.
That will tell you that you shouldn’t expect to spend more to save one life than estimated from the top charity; it might even tell you that the expected cost of the top rated charity is higher than the estimated cost from the next-ranked charity.
Without a reason to believe that the accuracy of the estimate for the lower-ranked charity is greater, you can’t conclude that the expected cost of the higher-ranked charity is greater than the expected cost of the lower-ranked charity.