The FAQ for NARA's NUMIDENT database says:
I.7. What are some of the limitations of the NUMIDENT Records?
The Application (SS-5) Files do not include records of all social security
applications between 1936 and 2007.
- Between 1973 and 1979, the Social Security Administration converted legacy SS-5 records to the NUMIDENT electronic database. Information on applications prior to 1973 may be incomplete.
The FAQ also says:
There are only Application (SS-5) records for verified deceased individuals or those born prior to 1908.
Since your person was born prior to 1908, it's reasonable to expect that the application would be in the database. However, the bullet point immediately above tells us that there are coverage issues before 1973.
It's also possible that someone who entered legacy SS-5s into the NUMIDENT database mis-transcribed or misread the name on the application form, so the application is under a name variant you didn't try. Searching by SSN should find any matching records but my experience is that searching by SSN (especially on Ancestry) doesn't always work.
Ancestry's FAQ says:
Last Residence Location
The Last Residence is the place where the person was last known to be living when the benefit was applied for.
This is what is supposed to be in the Last Residence field. Sometimes people doing data entry put information into the wrong fields. The Last Benefit is supposed to be "The [address] of either the Last Residence or the Lump Sum Payment." The Last Benefit address might be the address of a family member who lived at a different address. Keep in mind that if a data entry person accidentally entered the Last Benefit into the Last Residence field, or the website where you're viewing the data extracted the information from the Death Master File incorrectly, the Last Residence might be the City/State/ZIP of a family member instead of the deceased.
Assuming that the information in Ancestry's SSDI is accurate, we can see (working backwards in time):
- The person died in Aug 1970
- The last known residence was in Utah
- The application for the SSN was made via an office in Utah (it may mean, but isn't a guarantee, that the applicant lived in Utah)
- An applicant who applied in 1945 (to pick an arbitrary date) would have been around sixty years old.
To determine if this were the right person, I would try to establish their timeline -- when they married in Massachusetts, when they moved to Utah, etc. from other sources (including historical newspapers).
Possible future research:
The non-profit organization Reclaim the Records has made a records request via FOIA for a copy of the NUMIDENT SS-5 files and the NUMIDENT claim records files, requesting copies of the records "up to the present day, or as recently as is available."
Their page about the request says:
The current estimated completion date for this request is July 13, 2018. We’ll update this page as the situation changes.
Even if the data is the same as the NUMIDENT files offered by NARA's AAD, it will still be valuable to have another way of searching these records.