They were both traveling in the same direction?
Someone screwed up.
.
No it was oncoming....the duckboat went left of center and hit the bus on the driver side.
There is a pic on twitter up that shows the scene, and the duck boat collided with the side of the bus at an oblique angle. It looks to me like the bus may have made a lane change without checking/signalling and the duck boat couldn’t avoid it.