Caitlin says Kalanorians' brains have four hemispheres. Hemisphere means half of a sphere. Four halves of anything is an oxymoron. The correct word is quadrasphere. Since Caitlin is a scientist, a bio-engineer and a medical doctor, this isn't just a factual mistake, but also a character error.
It's never said that there was no one at the train station other than Joe when he died. The security chief that Iris and Allegra talk to merely says that the platform was "pretty empty"; there may have been a handful of people there, but it wasn't bustling with activity.
Jefferson Pierce a.k.a. Black Lightning mentions that Bill Henderson's sacrifice allowed him to return to his daughters in Atlanta. The series Black Lightning filmed in Atlanta but his town in the series was a location called Freeland.