I think you missed the point, or I didn't make it clearly enough.

In the case where someone values another's life so much they wouldn't trade it for an infinite amount of money, there's no mathematical model that can be devised that captures that, because there's no universe in which an infinite amount of wealth exists. Just like there's no universe in which we can convert meters to kilograms.

Yes, there may be circumstances in which we can equate money values to lives, but as long as there are any where we can't, the whole notion that somehow there is some universal equation that exists that we just haven't been smart enough to figure out yet is mistaken.