The University of Pennsylvania announced on Wednesday that the remainder of the women's volleyball season will be cancelled after finding "vulgar, offensive, and disrespectful posters" in the women's locker room.
The alleged victim of the assault did not give a statement because injuries left him unable to speak or write, police said.
One young woman claims Butler impregnated her and forced her to have an abortion.
Analysts spotted three volleyball games apparently underway at the Punggye-Ri site.
The jeers came a day after impeached former president Dilma Rousseff left office.
The swimmers, Jack Conger and Gunnar Bentz, have yet to comment on the incident.