Both have black on one side of the body. Try the X2 Florida grape as the second color 4 drops to 4 ounces of plastic, maybe add one drop of midnight blue to it. I little blue hi lite might look good in it too.
If memory serves me right the moccasin is a thin brown color with some pearl or hi lite in it to make it bounce a bit. Looking at the Culprit site its hard to tell from the pictures showing this color. If you have a worm take a picture of it and show us as a help on it. If no pic can be done I'd start with X2 motor oil at 6 drops per 4 ounces, a drop of amber to lift the lightness of it and gold hi lite. I'd go fairly strong with the hi lite but I'd add it a little at a time right at the end of the initial cook that gets you to 350 until the color has some serous reflectivity to it. I'd test it by putting heavy drops of it on the back of a mold and comparing that to a Culprit worm.
Hand pour or use a plate to get the un-vented side of the mold done in black, then inject the pretty color in to finish.
