This is reminiscent of NCIS (2003)'s Call of Silence (2004), for which Charles Durning was nominated for an Emmy. Gibbs took extraordinary measures to coax traumatic World War II memories from Durning's character in order to solve the case. And, as here, he did so as most of the team (plus the JAG officer) watched through the glass. Like Christopher Lloyd here, Durning was 81 years old.
Two more episodes were supposed to be filmed for this season but the show's production shut down due to the COVD-19 after this episode filmed. This episode became the season finale.
EMFA (Joe's rank) stands for Electrician's Mate Fireman Apprentice.
Gibbs goes by a man saying "Omar don't talk to me now". Omar is really Omar R. Lopez the actual director of NCIS.
McGee getting hounded by wrong-number calls is a callback to the same thing happening to Gibbs about a car for sale in Chained (2004).