Thanks for clarifying. The ELI5 on this is somewhat simpler: there isn't one yet, because it's the next step of the process (by design). Well-formed ballots are counted immediately after the deadline, then the updated voter rolls are made available to candidates. As you saw, the voter rolls include everything except how the ballot voted. Candidates can then dispute/contest ballots they believe are well-formed but invalid. For close races, they inevitably do.
In practice this means that both parties' national organizations have teams running voters' names through public databases right now, looking for dispute-worthy ballots/voters. I've never been a part of a national race so I can't describe the details of that, but my guess is they use the same data brokers as debt collectors, plus some data brokers that are specific to voter rolls. l2political.com is the best known of the political databases (details: https://guides.nyu.edu/l2political).
So, the ELI5 is: it's the next step in the process between receiving ballots and final tabulation.
(Source: Have volunteered as a ballot-counting observer in Seattle, volunteered for a local City Council candidate's campaign, and am leading a campaign to change Seattle's voting method. I'm nowhere near an expert but do know a lot more about it than most people.)
I guess my question is that there are thousands of records here where someone with a birth date from the 1800s were accepted, sent a ballot, then noted as received.
You can download 446mb of clearly bad data.