SAR Filing Regarding NAICS Codes (CTR)

I have a SAR filing question, regarding NAICS codes. We have an internal Quality Assurance Department that reviews all SARs filed in our BSA/AML Department. We are being advised to apply NAICS codes based on the type of industry an individual is employed in; For example we have an individual that is employed as a SCHOOL NURSE – I believe the NAICS code should be 6213 “Office of Other Health Practitioners​.​" However, my QA team is suggesting we use NAICS code 611 “Educational Services​.​” Other Examples Anesthesiologist with Conta Costa County we used 6213 “Office of Other Health Practitioners” – my Investigator was told to change this individuals NAICS code to 923 “Public Administration/Administration of Human Resource Programs, because the individual is employed with the County of Conta Costa. Or Accountant for New Beginnings we used 5412 “Accounting, Tax Prep” – my Investigator was told to remove 5412 and instructed to leave the NAICS code field blank because we could not definitively identify what type of business New Beginnings operates. I would greatly appreciate your interpretation or any reference materials like a previous FinCEN FAQ or SAR Activity Review Trends, Tips & Issues that would clarify or address this issue. ​