Your example is far more complex. The scenario he provided is easier to grapple with.
The patient (or whoever is paying the bill) and the provider determines the "worth". If they can't agree on a price, then it's not worthwhile.
In communism, would you really want to extract the equivalent of $50m of labour and resources in order to provide one person with this test? I can't imagine how that would be affordable.
Putting a monetary price on it in order to quantify the cost doesn't fundamentally change the equation. In the communist utopia I imagine it would be more like forcing x architects, engineers and builders to construct the facilities for the testing, x researchers and scientists to develop and conduct the test, x caregivers, plumbers, cleaners, drivers, baristas, chefs, etc for x weeks to provide this "free" test for one individual. Is that "worth" it?