Faded Yellow vs Golden Griffon

How close are they?

ΔE 21.1, loose: different enough that you should pick on purpose. Golden Griffon is a little darker, more saturated, warmer than Faded Yellow.

Can I use Golden Griffon instead of Faded Yellow?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 21). Golden Griffon is a little darker, more saturated, warmer than Faded Yellow.

Can I use Faded Yellow instead of Golden Griffon?

The same difference applies the other way round: Faded Yellow is a little lighter, more muted, 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.