It's undeniably tragic that three little girls were run and killed on Halloween night in 2014 as they crossed the street in a marked crosswalk. The person who hit them fled the scene but was captured two days later.
The dissent says that the accident might have been caused by a tree that cast shadows that evening onto part of the crosswalk. But that's the dissent.
The majority says there isn't a genuine issue of material fact; the shadows didn't cause the accident, which was instead caused by a hit-and-run driver who was going between 50 and 70 miles per hour -- on Halloween evening, no less -- on a street that had trick-and-treaters dressed in all black and a posted speed limit of 25 mph when kids were present (and 45 mph otherwise).
Just because you have an expert doesn't mean that you'll necessarily get to trial. As here.