The butler, who is supposedly very intelligent for the position he is in, does not seem very intelligent to be pissing whom he perceives to be the next head of the family and his future boss. It won't be surprising to see him drowned and frozen in a frozen lake in the middle of the desert. Tatsuya and Miyuki have been hinted to kill others before, so it's not beneath to off an "enemy". Plus, considering that they are part of the 10 elite families, they can easily sweep this under the rug.
There were many things in this episode with bits and pieces of information. It will require a second viewing to digest it all.
My guess is either Miyuki will cast an ice wall or Tatsuya will swoop in front, dispell all cast magic, and cast a forced push off spell.