ΔE 10.8, fair: the same colour family, but not a straight swap. Rotten Flesh is a little darker, more saturated than Mummified Grime.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Rotten Flesh is a little darker, more saturated than Mummified Grime.
The same difference applies the other way round: Mummified Grime is a little lighter, more muted.
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 Mummified Grime on the colour wheel See Rotten Flesh on the colour wheel
All matches: Mummified Grime equivalents · Rotten Flesh equivalents