If you think the scores are off and you can afford to retest, you might as well. I'm not a fan of score-chasing, but I also think that one test on one day with "flaky" tests at the tails can make for scores that aren't telling the whole truth.
Count us in the "retest and score higher" group. DS7 (then 6) had a bad test day for several reasons (lack of 2-3 hours of sleep because of an overstimulating hotel stay, stomach flu with fever that showed up about a day after testing, bad test fit with the SB-V, etc.). As a result, our tester--one of the nation's top experts on GT kids--felt the scores were lower than DS7 was capable of. He suggested we wait a few months and retest locally with the WISC instead. We followed this advice and he scored in the DYS range on the WISC.
A test is just one score (or set of them) on one day. If the number doesn't match what you see, then I think that trying again makes sense. But unless you have the scores, I don't think I'd recommend applying to DYS yet. They are pretty strict about the score cutoff. I wouldn't waste the time until/unless you have the numbers.
