Just did the MMI. It was super fun - something I never expected to say. All were scenario-based except the "Sell Yourself." Really, just relax. It was so chill, and everyone was so nice. I had some thought-provoking questions/scenarios I thought were genuinely interesting (but not challenging to answer!) and scenarios similar to the ones on Casper. I definitely overprepared, so don't overthink it.
They want to get to know you. You also have three whole minutes to read and prepare; it's a lot of time. I had some wonderful conversations with some of the students and faculty. Tip: always have questions ready in case there is extra time remaining at the end. They are so kind and personable, honestly, UTMB has gone higher on my list of schools to attend after that interview. You will all be okay!
Funny story: I'm in a different timezone than CST right now, so when I got on, I was saying "Good morning" to the interviewers, and noticed a bit of confusion, and couldn't figure out why (it was afternoon in Texas smh), until I met the fourth interviewer, a super kind lady, and told her "Good morning..." she asked me "Is it morning where you're at?" I just laughed and said, "Yup, I just realized I have been saying 'good morning' to everyone before this," and we had a great laugh together. It was a great icebreaker. They are so so kind.
TLDR; just like Casper, SDN questions helpful....the only way you will succeed is to stay comfortable and confident in yourself.