First on a pass from the post to the wing it came close to Toolson and from my angle, it looked like it was out on Toolson, but he was telling the ref he didn’t touch it. He jawed with the ref a bit and while that was happening, there was a timeout. The Loyola player was headed to the bench and he bumped Toolson from behind as Toolson started to step left. It looked unintentional, but I think Toolson thought it was on purpose and pushed the dude in the back
Not sure if there was something else prior that led to the jawing, but from my perspective it all seemed to be about the call where the ball was called out on Toolson.