No. Voting history may show that a person voted in an election, but ballot choices are secret and never recorded with their name.
It depends on the state. Some restrict access to campaigns, researchers or election-related purposes, and many prohibit commercial use.
A state program that keeps the addresses of survivors of violence and certain others confidential, including on voter records.
Not by itself. Clerical and matching errors occur, so raise it with election officials and investigators for verification.
County election offices, county archives and historical societies may hold older poll books and registers.