What are the correlations between the facets of honesty-humility in HEXACO personality and the Dark Triad?
Lee and Ashton (2014) write:


  A few studies have directly examined the relations of the Dark Triad
  with the Honesty–Humility factor (as operationalized in the HEXACO
  Personality Inventory [–Revised]; HEXACO-PI[-R]). These investigations
  have found the low pole of the Honesty– Humility factor to be
  essentially identical to the common elementof the Dark Triad variables
  (Lee &amp; Ashton, 2005; Lee et al., 2013).


One study I found by Aghababaei et al (2014) reports the following correlations for 223 employees using 12 item dark triad and 60-item hexaco.


Of course, this is not the ideal study for facet-level measurement of honesty-humility. Ideally, you'd want more items both for facet-level measurement and measurement of each of the dark triad in order to get a broad and reliable measure. But it should give some idea.

References


Lee, K., &amp; Ashton, M. C. (2014). The dark triad, the big five, and the HEXACO model. Personality and Individual Differences, 67, 2-5.
Aghababaei, N., Mohammadtabar, S., &amp; Saffarinia, M. (2014). Dirty Dozen vs. the H factor: Comparison of the Dark Triad and Honesty–Humility in prosociality, religiosity, and happiness. Personality and Individual Differences, 67, 6-10.