Consider how much time you have spent trying to locate that one record. It might be time to work on something else. I have a relative for whom their life from 1847-1855 is documented in several records, marriage, land purchase, declaration of intent, 1855 state census, probate, and guardianship for children. Yet, I cannot find him in the 1850 census.
In this case, it might not be worth it to spend days searching for him in the 1850 census. Just a thought.