[BiglyCommentary]

First, let me say that I would bet my very life there was cheating in all areas, in every way possible.

Now if those image timestamps was the create date of the file, simply copying the original files from the original system to elswhere could produce this. Scanner scans at lets say 1 ballot every 5 seconds. Files timestamps are 5 seconds apart. Those files are copied across a LAN, copies have timestamps milliseconds apart.

[kiryandil]

Those files are copied across a LAN, copies have timestamps milliseconds apart.

The "non-networked machines" are part of a network.

Got it!   

   

[BiglyCommentary]

5 scanners dumping fhe images into a common network folder could produce the 5 to 7 ballots with same second timestamp.

This could wind up being a nothing burger if that was the setup.