Sorry Cas I should have been more clear. They have very rickety tables with very rickety privacy dividers where you fill out the scantron, then take it to the tabulation machine and feed it in using the privacy envelope. There's only 1 machine involved.
I am bad at following directions and accidentally submitted a spoiled ballot (voted for too many candidates in one section) and the tabulation machine knew it and notified me. I thought that was cool and interesting, the machine is applying some quality rules and thresholds on ingestion.