This looks just like a normal reconciliation
They're doing a hand recount of millions of ballots.
The guy goes in and he counts out his ballots. Afterwards they look at the total tally and they realize that there must be some missing because the hand count doesn't match at the tally count. So he goes back to the box for the batches to find the box that he did not count. They will then have to recount that batch again.
Once again nothing happened. This is a very normal part of any recount. they do these in batches and they compare them against the number of voters that checked in to those precincts involved.
If your total number of votes hand counted matches the total number of voters that checked in then you can be confident that you have recounted all of the relevant votes.
This is now the third time that this tactic has been used to imply something went wrong. This is in fact a normal part of every single election at this size. This is pretty much guaranteed to happen through the steps of any hand recounts.