For an Entity X how can I check the authed players for the TC that protects Entity X?

look in BuildingPrivlidge for more info but here is how to get the priv and see if player is authed.

BuildingPrivlidge theBlock = entity.GetBuildingPrivilege();
if (theBlock != null &&theBlock.IsAuthed(player.userID))
{
     //do somthing
}