ΔE 10.0, fair: the same colour family, but not a straight swap. Death Korps Drab is a little darker, more muted, warmer than Rock Grey.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Death Korps Drab is a little darker, more muted, warmer than Rock Grey.
The same difference applies the other way round: Rock Grey is a little lighter, more saturated, cooler.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Rock Grey on the colour wheel See Death Korps Drab on the colour wheel
All matches: Rock Grey equivalents · Death Korps Drab equivalents