It doesn't sound like the report reached a conclusion about the drug testing, one way or the other. Here is what the report actually says about drug testing (page 15):
Numerous individuals also raised more frequent drug testing of Black players as a concern. Athletic Director Barta told investigators he became aware of these complaints in June 2020 and he and his staff have started a review of the Department’s testing protocols and will work with the outside vendor, Aegis, to improve the process. The Program Manager in charge of student-athlete drug testing told investigators that testing staff does not know the race of individuals selected for testing. Student-athletes are tested randomly and if they have previously tested positive or produced a diluted sample they may be selected for further testing. The Program Manager reviews the lists of players selected for testing and removes individuals who have been tested more frequently. She explained that the Head Coach may also request that specific players be tested, but the coach must have a legitimate reason for making such a request and the request must be reviewed and approved by the supervising physician before the player will be tested. Head Coach Ferentz acknowledged that changes need to be made to the program’s drug testing policy, but he denies that Black student athletes are tested at a higher rate. He reviewed the testing data from the 2019-20 academic year and determined that three players were tested three times. Of those three players, two were White and one was Black. He identified additional ways that the testing program could be improved to provide more privacy to players. Currently, the Program Manager administers the testing program within the football building, and Head Coach Ferentz intends to remove testing from inside the football building moving forward.
What are needed to make a conclusion are the actual data (number of times tested and/or probability of being chosen for tests) for every player on the team. Then, and only then, can we make a conclusion about whether or not the testing process was truly random. BTW, I bolded a few lines that drew my attention. If Ferentz can select certain players for testing then that could easily skew the testing rates, even if the testing agency's selection process is random.