Rule 10.08 governs the scoring of sacrifice bunts, and the phrase "double play" doesn't occur in that rule.
If the batter is put out, was judged to be bunting for a sacrifice, and at least one runner advances one base, it is scored a sacrifice, except if any runner is put out before advancing one base.
Maybe the other scorer was confused and thinking of RBIs. A batter is not credited with an RBI if he grounds into double play.