If you search, there are other threads out there for the MWU-IL interview. They basically say that there is no real way to prepare for the interview. The interview is like speed-dating style, where there are five-ish rooms and each room has a scenario.
You stand outside to read the scenario for 2 minutes, then go inside the room and discuss it with a faculty member for 8 minutes. Buzzer sounds, and you move to the next room-five-ish times.
So.. just be yourself!! There truly is no way to prepare for this type of interview, so relax and answer to the best of your ability. They mentioned something about wanting to see your conversational skills and your critical thinking ability.