You never know. Not completing an application, not sending in a score, isn't exactly going to work in your favor -- but on the other hand, if your file is complete when you are looked at by the Admissions people (and they don't look at all files at once, of course, but over many weeks and months), they are not very likely to care. Every year, lots of parts of applications get mislaid, lost in the mail, or forgotten. It's pretty normal, and Admissions people understand how busy high school students are and how many different things they have to send in. So, I wouldn't worry too much about this. I imagine that your file will be complete well before they will have completed their list of acceptances.