That's not happening here, enabling/disabling the "simulation object cast shadow" option doesn't make any difference.
What can make a difference, is enabling the "No shadow flagged content" option instead, which should be ALWAYS turned off because, what that option does, is to override the settings in the scenery to prevent some objects to cast shadows which will result in problems, since if a scenery developer has disabled shadows for an objects, there's usually a good reason for it.