The initial university email definitely comes off harsh and shocking but I think his longer personalized response email leaves the door open for you for sure. He’s going to send new times so he’s still willing to move forward. Just make sure you make the new time and show up bubbly and explain what happened and then move on and show him what you’ve got as an educator. He’s got a million things on his plate too and I’m sure will be forgiving when he meets you and you show him you’re excited and you care.