Paper ballots
In person voting
Tight ballot control
Then for counting - manual ballot count. Packets of ballots (maybe 50-100). Each counter reports their count for that packet. Then it's sent back out for a different counter (maybe 3 total minimum woth at least one counter from each party, possibly). You keep sending out the ballot packets until there is statical agreement. Any counters with repeat mismatched to others will be removed.