ΔE 14.0, fair: the same colour family, but not a straight swap. Stormvermin Fur is a little darker, much more muted, warmer than RAL 7009 Hellgrau.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Stormvermin Fur is a little darker, much more muted, warmer than RAL 7009 Hellgrau.
The same difference applies the other way round: RAL 7009 Hellgrau is a little lighter, much 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 RAL 7009 Hellgrau on the colour wheel See Stormvermin Fur on the colour wheel
All matches: RAL 7009 Hellgrau equivalents · Stormvermin Fur equivalents