The suede will turn darker with the application of the resins or any liquid. As Seamus said, even the darkest color of leather will darken some. Even when a waterproofing grease/wax prep is applied it will darken the leather.
You have to remember that leather has a burnished surface finish, and suede. Due to its textured nature and open pores, suede may become dirty and absorb liquids quickly. Because suede does not include the tough exterior skin layer, suede is less durable but softer than standard ("full-grain") leather. Its softness, thinness, and pliability make it suitable for clothing. Suede is made from the underside of the skin, primarily lamb. The splits of beef and deer give a shaggy nap, not as smooth.
If you can live with the color shift, wetting a scrap of the suede or leather will give a pretty good indication of the color.
:clown: