This is because it is a technical hockey term and not an ordinal number. The hole is named the 'five hole' we are not just counting holes. It is different to golf.

Hello! In hockey, a five hole would be the place in between the goaltender's legs. If I were to shoot the puck in between the goaltender's legs, I would have scored 'through the five hole' In this sentence, we can imply that the main character is screaming to another person to aim for the five hole. Hope this helps! :)