Explain "fake paper votes". I'm not sure that this is a real problem with normal auditing -- record all voters that come into a precinct, what time they appear, and compare to the number of received ballots. Comparing signatures of voters to the file signature is common for absentee voting. It's just far harder and riskier to mess around with compromising paper ballots than a mistake (or "mistake") in a line of code.
You cannot force voters to come in and confirm that they sold their votes for exchange of money. They will lie. You must catch fakers, which is tricky when they have chance to win election and punish you, like Stalin did.
