ΔE 15.8, loose: different enough that you should pick on purpose. Frostbite is a little lighter, more muted than Doomfire Drab.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Frostbite is a little lighter, more muted than Doomfire Drab.
The same difference applies the other way round: Doomfire Drab is a little darker, more saturated.
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 Doomfire Drab on the colour wheel See Frostbite on the colour wheel
All matches: Doomfire Drab equivalents · Frostbite equivalents