In response to previous discussions, I understood that we had all agreed to have a computationally understandable way to indicate prior authorization requirements.

It seems like this new section http://build.fhir.org/ig/HL7/davinci-crd/hooks.html#linking-cards-to-requests was introduced towards this in view. 

However, IMO this fails to meet the need. 

We can understand that a specific card is about specific order(s)

But we cannot as far as I can see understand either that the card is about prior authorization (unless we standardize card.source.topic, which today isn't a standard) nor computationally / semantically understand what is the covered status / prior authorization requirement(s) on these orders.