I happened onto your web site in search of a definition of the intent of the word "curse" as used in Job. I do have a question for you. If the book of Job was written before the Levitical priesthood was established, which would explain why Job, himself, made offrerings for his children, then the references you give from the times of the kings rule would not be applicable. Would you agree with that? No disrespect intended.
It is true that Job did not live under the Mosaical laws, but we are not discussing laws here. We are discussing the meaning of a Hebrew word. Words do shift meaning over time, but we can gain understanding of how a word was used and what people saw it to mean by looking at how it was used before, during, and after the time period in question. For that purpose, citing how the word naqab was used in a negative sense throughout the Old Testament period gives us a better understanding of how it was being used in Job.