Due to the farcical Irish reserve rule all the bookmakers had different rules regarding the race. Corals priced up all the runners including reserves with a rule 4 for any nrs. Presumably their prices would have been bigger overall to compensate for this.
I didnt pay much attention to the article but on the Pricewise page on the day of the race he stuck up bookmakers changes to terms and prices had Beutiful Sound got in