Oozing Vomit vs Moldy Ochre

How close are they?

ΔE 16.0, loose: different enough that you should pick on purpose. Moldy Ochre is a little lighter, much more saturated than Oozing Vomit.

Can I use Moldy Ochre instead of Oozing Vomit?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Moldy Ochre is a little lighter, much more saturated than Oozing Vomit.

Can I use Oozing Vomit instead of Moldy Ochre?

The same difference applies the other way round: Oozing Vomit is a little darker, much 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.