Are you saying they refused to upload all info to include criminal history information or just missing person info? If it’s all info, that is messed up. Is there a state level system AZ uses and maybe they were putting the info there?
When the NCIC first came into being there were something like 150 questions that to be addressed for each crime. Agencies balked at this stating they didn't have that kind of manpower to put an division of personnel to work entering data. Since then, in response to LE concerns, this has gradually been reduced over the years. The last I heard this number was something like 20-25 questions. But, yes, Scottsdale stated they didn't have the manpower.
As to enters into NCIC (for most criminal files), 1.4, #1 of the NCIC Operating Manual:
"Most records are placed directly into the NCIC 2000 System by an originating agency (agency holding warrant, missing person report, or theft report; registration information on convicted sexual offender, convicted person on supervised release, etc.), through a control terminal tied into the network."
(Other files such as those persons making threats to the President are controlled and entered by the Secret Service, immigration cases by INS and foreign cases by either RCMP (Canada) or INTERPOL reps in the USA.)
1.7, #2 of the NCIC Operating Manual states:
"Although the use of NCIC is voluntary, delayed entry of records in NCIC reduces or eliminates the possibility of apprehending wanted persons, locating missing persons, and recovering stolen property."
So even the operation manual acknowledges that the use is voluntary.
With regard to responsibility for the data security entered the manual stated this in 1.6, #3:
"The FBI uses hardware and software controls to help ensure System security. However, final responsibility for the maintenance of the security and confidentiality of criminal justice information rests with the individual agencies participating in the NCIC 2000 System."
As far as non-Federal LE agencies interfacing with NCIC, I have no idea to what extent they are compatible. Some entities have dropped their systems and use the NCIC exclusively. But generally speaking state agencies enter data for cases where they have jurisdiction only.