In 40ish years of watching NFL since it first aired on channel 4, I've never seen a helmet break like that. You have to wonder if the extreme cold had anything to do with it.
Mahomes wasn't pulled for a concussion check btw.
I've made a point of having it at times while Bob was playing and haven't heard him mentioned once never mind see him hit a shot. You could say the same for about 3/4s of the field though.
I gave up at half time. The Dolphins were awful. Defense had kept them in it by keeping the Chiefs mainly to field goals, but throwing screens that your receivers kept dropping anyway isn't going to get you very far.