ΔE 14.1, fair: the same colour family, but not a straight swap. Undead Flesh is a little lighter, more muted, warmer than Ogryn Camo.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Undead Flesh is a little lighter, more muted, warmer than Ogryn Camo.
The same difference applies the other way round: Ogryn Camo is a little darker, 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 Ogryn Camo on the colour wheel See Undead Flesh on the colour wheel
All matches: Ogryn Camo equivalents · Undead Flesh equivalents