In the US. Public domain dedications have no legal standing in most of mainland Europe's IP regimes. A public domain dedication is the equivalent of no license at all.
And because a public domain dedication has no legal standing, a third-party slapping a license on the code does not make it legally licensed as far as european IP courts are concerned, they don't have that right, their "license" is worth as much as you deciding to license Windows under GPLv3.
> But if you think you need it licensed, you can have it licensed.
Unless djb offers to provide a fallback license (which incidentally is exactly what CC0 does and why it's legally sensible and valid[0]), then no, you can't "have it licensed".
[0] https://rd-alliance.org/sites/default/files/cc0-analysis-kre...