It was mailed from Columbia , Massachusetts with 41 cent stamps, not even a postage meter stamp.. so... I am sure that whomever mailed these the Post Office will have video of it.
CORRECTION columbia , south carolina..strike the Massachusetts.
> I am sure that whomever mailed these the Post Office will have video of it. <
It’s best not to be so sure. What about the person who mailed the anthrax letters in 2001? The postal inspectors and the FBI don’t seem to have had any videos in that case.
(But maybe the USPS has installed a lot of cameras since then?)