Is the PMIX/NIEM format already in place for the majority of States? Is this a mandatory requirement that PMIX/NIEM be used?

Is NIEM an ANSI-recognized standards should we even be using a non-ANSI-recognized entity in an HL7 standards…
How have they validated their translanted between HL7 or NCPDP?

Existing Wording:

The intermediary typically converts this incoming NCPDP request to PMIX/NIEM format and initiates a request to the State PDMP systems