6.42% was the total rejection rate for all causes. Most ballots are rejected because they arrive late. Those are not yet included in the 2020 reject numbers.
The factcheck article is from November 20th.
The Ballot tabulation website page says it has been updated December 9th (today)
Its been weeks since the election, We don't even know how many votes have been cast still?
This seems ridiculous. Most countries have final results on election night.
Georgia 2016 6.42%
Georgia 2020 .60%
Source https://ballotpedia.org/Election_results,_2020:_Analysis_of_...
Which cites the official Georgia election website as source of the raw data.