The subplot of this episode, Sharona's terror of the elephant, is similar to "Wings (1990)" (which Tony Shalhoub starred in) called "Oedipus Wrecks (1997)". Tim Daly, who plays Joe, is terrified of an elephant as well.
Steve Monroe, who plays Sgt. Myers, also played another character, Chet Walsh, in S7:E13 "Mr. Monk Makes the Playoffs (2009)."
[20:19] Monk says to Sharona, "You know who you should never marry: the Elephant Man." This is an allusion to Joseph Carey Merrick, a performer in Victorian-era Britain during the later part of the 19th century. He was born with deformities so severe that he was exhibited as a human curiosity known as the "Elephant Man." Monk is being rude about her phobia of actual elephants.