The “Patterns Interface” section of the Decker docs describes the animated patterns as:
A list of up to 256 pattern indices for animated patterns.
You can include solid “red” and “black” in the animated sequence because they have pattern indices (35 and 1). But if you want a pattern pattern, those are described as:
An 8x8 image interface comprised of patterns 0 and 1.
So actual patterns can’t have red in them, only patterns 0 and 1, which are (by default) white and black. You could set palette 32 to be red instead of white to get red-and-black animations, but that would make every white pixel red, which probably isn’t what you want.