"The University of Illinois is also in turmoil. The university sports an Interim Chancellor, an Interim Athletic Director, and an Interim Football Coach; the game will be played at Soldier Field, making this an Illini Interim Home Game."
its potentially a non-issue. He could technically be accepted despite not passing the graduation exam. Its up to the school, because the certification from the exam is separate from his GPA and test scores. Being Michigan, thats probably not a possibility though.
Also, the test is 6 parts and from what I understand he had issues with just one part. I would agree this probably won't allow him to start summer classes, but he's got at least two chances to rectify this situation before August.