Phil Wood and Kowa spoke machines cut 10mm of threads - and in your case 12mm nipples and 14mm nipples would have worked.
However you mentioned use of DT Swiss spoke machine? With 9mm threads? 12mm nipples might take up the slack and stop at the top - but don't think 14mm nipples will work.
Good Luck!
=8-)
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5000+ wheels built since 1984...
Disclaimer:
1. I do not claim to be an expert in bicycle mechanics despite my experience.
2. I like anyone will comment in other areas.
3. I do not own the preexisting concepts of DISH and ERD.
4. I will provide information as I always have to others that I believe will help them protect themselves from unscrupulous mechanics.
5. My all time favorite book is:
Kahane, Howard. Logic and Contemporary Rhetoric: The Use of Reason in Everyday Life