This episode is the second time Homer acts as a soccer referee. The first was in "Marge Gamer". The events of that episode were mentioned in Lisa's Speech. Also, in both times, he has trouble dealing with floppers (Lisa/El Divo)
The player that dives and "breaks his leg" is based on Barcélona player Neymar who in real life is a known diver.
Lisa's speech also mentions Homer working two jobs to get her a pony ("Lisa's Pony") and started her playing the saxophone ("Lisa's Sax").
Homer says that Rio is the naughtiest city ever since San Francisco got all nerdy.
In Nelson's speech he mentions a chained up man cutting off his own foot to save his family from Jigsaw. Referencing what happened in the movie Saw and he says that he saw this because his mom's old boyfriend took him to an R-rated horror film when he was 3.
The Stuffwich ads featuring Ezra are a reference to the Subway ads featuring Jared Fogel.
The man who offers the match-fixing bribery to Homer, gives him the pirated copy of Man of Steel, a 2013 superhero movie about Superman.
One of the certificates in Skinner's office is from Springfield Diploma Mill, which a reference to real life diploma mills, which universities which offer fake degrees for a fee.
When Lisa is trying to think of a person to give her speech on, "Heroes" by David Bowie plays in the background during a brief montage.
According to the Newspaper shown after the student's fight, it ended only after one student: Ralph Wiggum, was left alone, punching himself at the gym.
References to the World Cup
The World Cup, despite being a central point of the episode and the World Cup tournament as a whole, does not appear and is not seen in any way.
FIFA is not mentioned in any way.
The logo is distinct from that of the real FIFA World Cup, as does the name.
It is unknown which team was the winner of the World Cup in-episode, but it seems to be Germany, as Brazilians go sad out of the stadium when the match presumably finished.
The celebrations of the teams winning are not shown.
The episode parodies how corrupt are some referees in real life, specially parodying the fact that most referees in the real FIFA World Cups where Brazil is the host, do some 'favors' in Brazil's side.
This episode managed to accurately predict the winner of the the real World Cup (Germany).
Marge was using an app on her tablet to learn Portuguese, however this would require internet, but portable electronic devices have to be in flight safe mode for the duration of the flight.
In recent years, some airlines have introduced in-flight wifi, so this might be a goof per se.
In the exterior shot of the plane, it is too low to be at cruising altitude, but it is too far from Rio de Janeiro to have begun its decent.