If this video depicted what was being shown in the captions accurately, it would have been discovered when the hand recount was done. Seeing that there was no discrepancies, the more likely scenario is that the machine wasn't reading the ballots correctly (notice how she kept stacking them together) and she wasn't to ensure the tabulation was correct, thus doing it multiple times.

Also, its not like when a ballot is scanned it instantly goes to the "results" number. They look at how many ballots the machine says and it is manually inputted into the system.