Looks like the DYS website has a Q&A page. http://www.davidsongifted.org/young...rs___Frequently_Asked_Questions_381.aspx

Q. What if my child does not meet the minimum qualification criteria?
As we strive to serve the extreme of the gifted population, the scores listed on our website are considered to be the minimum in terms of eligibility requirements. However, we recognize that testing is only a small snapshot of a whole child and we take the entire application into consideration when determining eligibility. If the tester feels there were extraneous circumstances preventing a child from meeting the minimum criteria, a letter from the tester included with the application to explain the test scores will be considered in the review process. Many very bright students may not meet our qualification criteria for this program, but are likely to benefit from the information and resources that the Davidson Institute makes available to the public via our websites, including our searchable Davidson Gifted Database, the public Gifted Issues discussion forum, and several guidebooks.

Q. What is the review committee looking for in a portfolio?
The committee is looking for a portfolio that will, in essence, override the absence of IQ or achievement scores. Work samples need to clearly demonstrate the child is working at least two to three grade levels above age peers in academic areas including math, science, social studies, or writing. The Review Committee prefers handwritten examples as they allow them to better gauge the child’s level of ability and independence. However, you can submit typed assignments with teacher grades and comments. Each work sample should include the date and age of the child when it was completed as well as the context for when and how the work was created. You can also submit workbook pages that are two to three years advanced for the student’s age.

It can't hurt to apply with additional portfolio items, but I would include the current scores as well. I don't mean to be unsupportive, and tend to agree with lucounu that they appear to have a wider net than the name and score cuts suggest. I should probably suggest several of my students apply, as I have several in this range.