The liquor that Joel and Sheila bring to Mrs. Bakavic is Maraska-brand Sljivovica, a plum brandy popular in Central and Eastern Europe. It is the national drink of Serbia. It is produced in Croatia from plums grown in Bohemia.
This episode marks the reunion of Timothy Olyphant and Portia de Rossi who were both in Scream 2 (1997).
As another user has noted, Abby's room has a giant poster of Australia, and Liv Hewson is Australian. However, so is Portia de Rossi, who plays Dr Wolf, and she is staying in Abby's room.
Drew Barrymore, Timothy Olyphant and Portia de Rossi have starred in the Scream horror franchise: Barrymore in Scream (1996) and Olyphant and de Rossi in Scream 2 (1997).