ΔE 8.9, close: similar, with a visible difference side by side. Death Korps Drab is a little darker, more muted, cooler than Dark Mustard Khaki.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Death Korps Drab is a little darker, more muted, cooler than Dark Mustard Khaki.
The same difference applies the other way round: Dark Mustard Khaki is a little lighter, more saturated, warmer.
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 Dark Mustard Khaki on the colour wheel See Death Korps Drab on the colour wheel
All matches: Dark Mustard Khaki equivalents · Death Korps Drab equivalents