Could ice have broken up the rocks here, like with glaciers? I know the ice couldn't actually flow here because it's so flat but could rocks have been transported on ice and then deposited when the ice melted/sublimated?

If there was a flood here then it's likely it was very cold. So rocks may have been carried along in an icy flow. This would tend to scour the ground and then the rocks would drop down when the ice melted.

I read once there was evidence of this at one of the Viking sites, where the rocks formed a pattern often seen with melting ice. A large rock falls thorugh the ice and smaller rocks fall in the hole around the large rock.