Yeah I was wondering the same thing. However, after looking more closely, I think the price is $20 per county. So it would be more like $1340 total. I am guessing that is what the original dataset poster paid.
I have found similar results to you. I used the same dataset you linked in your post. I checked everyone I know that voted in person and it does not show they voted for this election. Perhaps the dataset was downloaded too early. I did check one person that voted by mail. This person shows as voting on Nov 3. I guess this makes sense since the ballots were only supposed to be counted on Nov 3. For reference, people can pay to download the voter info here:(https://www.pavoterservices.pa.gov/pages/purchasepafullvoterexport.aspx). I assume that is where the original data set came from. This page mentions that it is up to date for Nov 9 and will be refreshed Nov 16.
Sorry, yes that looks possible for just $20! I was just thinking big picture and auditing the whole state, haha!