There is no such thing as "unverified mail in voting". Every mail in ballot has to be certified and properly cast to the counted.
Mail in balloting has existed since the Civil War and there has never been any major fraud involved in mail-in ballots. Republicans have been the leaders in mail-in ballots for decades. It was only after Democrats discovered the ease and convenience of mail-in ballots during covid, that suddenly Republicans were claiming mail in ballots were rife with fraud and endangering democracy.
It should also be noted that since 2013, Republicans in red states closed more than 1000 polling stations located in inner cities close to public transit. In one district, they moved the only polling station in a black neighbourhood to a location outside the city limits, which could not be accessed by public transit.
Top three states for closures were Texas, Arizona and Georgia as the trend has accelerated, with 69% occurring after 2014 midterms
www.theguardian.com
This is why you see hours long lines at inner city polling stations in the south, while suburban residents are in and out in 5 minutes. And why so many Democrats are
now using mail-in ballots.