"Can it be said with certainty that the vote discrepancy arises only from paper ballots?"

The chair replied:

"Yes, human intervention is definitely a factor. Using both online and paper (as directed: - ) was a huge challenge when trying to do the total number of ballots - I THINK that is where the count is off -- we'll see. I did find an error on the report already- the 18 duplicates were NOT counted towards the total of paper ballots received, but they were counted in the total candidate votes."

At the very start of my research on the election report, I had the chair explain to me the meaning of "duplicate ballots":

"The title "duplicate ballot" refers to the paper ballots issued to those who did not receive their mailing, or those that went to their primary residence but they were in Ocean Pines and wanted to vote, etc. so duplicates are counted and scanned."

I think "replacement ballot" would be a more appropriate name for her description of "duplicate ballot."

If, as the chair says above, "the 18 duplicates were NOT counted towards the total of paper ballots received, but they were counted in the total candidate votes" that would mean that the ballot total was 2857 (2839 + 18 = 2857).

If that is true, the 18 duplicate ballots could, AT MOST, account for 54 votes (18 ballots X 3 maximum votes per ballot = 54 votes) of the 536 vote discrepancy that I first documented. That would leave a 482 vote discrepancy remaining (536 - 54 = 482). 

[As Ive pointed out previously, it is important to remember that the calculated discrepancy represents a MINIMUM discrepancy because it is based on applying the 3 vote-maximum to all ballots.  There is a possibility (probability?) that some ballots had less than 3 votes. The presence of ballots with less than 3 votes would reduce the maximum number of votes that could be arise from the ballots cast and that reduction in the maximum number of possible votes would INCREASE the discrepancy with the number of votes counted and reported.]

Finally, it is to be noted; the counting error of 18 ballots involved paper - not online - ballots.