Well, that switch is common cathode (negative), so you won't be able to have it wired in parallel your blade. The Prizm would require you to have a common anode (positive) led if you wanted to wire it in parallel with you main blade LED.
Check the manual though, because I think it has a diagram for wiring a common cathode led from the PWM signals so you can have a blade matching LED, so that may work for you.
Your other option is to just wire the R, G, and B to three of the accent pads and use those. The color of the switch would then be determined by your accent led definition in those files.
You'll only want to wire one switch to the accent pads though. Those accent pads only put out like 18ma or so, and you'll probably want to use all of that for just one switch.