@CountryMage The rules of physical objects made by magic are always wonky. The best example is probably the earth element, where generally aside from sometimes poison, almost everything earth magic makes is physical objects like sand and boulders, but still you'll have stories/games where people weak to the earth element get hurt more from being hit by a giant earth rock than a giant ice rock, despite our non-magical assumption being "well the magic is hitting their armor/clothes, not them physically, so it should just be the concussive force of the rock doing the same damage". Especially when the fantasy world is based on video game mechanics like this one, factoring element into the object being made isn't too crazy imo.
I think it's best to go with author intent and not physics here, if she was intending to kill him and not herself, it means the ice meteor wouldn't have been a problem for her. They probably assumed it wasn't necessary to go into the in-depth explanation of why it wouldn't have, with minor things that can be pieced together into a reasonable explanation there. It's like seeing a MC get punched by a super powerful demon while standing still and not moving an inch and thinking "that's wrong, even if he didn't get hurt, he should've went flying because of the force of the punch and his relatively low mass without being anchored". Supernatural abilites and natural physics don't mix perfectly.