You're stating your opinion—to which I'm sympathetic! For obvious reasons there are no "facts" about the Framers' views on DNA testing. But our opinions and interpretations don't determine what rights are actually recognized and enforced; the Supreme Court's do.

On the interpretation that is actually applied in American courts, obtaining a genetic sample does not count as "compelling" a person to "be a witness" against himself because (like a fingerprint) it is "non-testimonial". If the sample is obtained by intrusive means, like drawing blood, a search warrant is required—though, of course, DNA can often be obtained without such intrusion.

You are, of course, free to disagree with that interpretation, or to speculate that the Framers would have had a different view had they lived to see the era of genetic testing. But the rule currently applied by all U.S. courts is that the Fifth Amendment protects against self-incriminating testimony, and does not cover biological evidence.