My take on the situation was the rules official used the range finder to determine the equidistant point on the opposite side of the hazard, but did not divulge the yardage to the player or caddy.
Mike, since the hazard was not designed to be crossed during the regular play of the hole, marking as a lateral hazard is appropriate, but that does not eliminate the ability to declare it a water hazard. Also, the drain is an immovable obstruction, and at that point not within a hazard line. If there is certainty that a ball enters an immovable obstruction is does not have to be found. Relief is at the entry point.