Is there really no way to eliminate the on camera flash for the OM-D?

Is there really no way to eliminate the on camera flash as a light source for the OM-D?

I find that the small flash when used as a trigger (wireless FL0600R) still contributes to exposure even when set to OFF in the flash control panel.  I came across this in the OM-D manual:

"If the subject is too close to the camera, the control flashes emitted by the camera flash may affect exposure (The effect can be moderated by reducing the output of the camera flash using a diffuser or other similar techniques)."

Has Olympus really not figured this out?  Annoying if you want to eliminate the fill on close subjects.  I've been bouncing off a card.  Anyone find a way around this?  I actually find it adds more light to the exposure when the on camera flash is set to OFF than when it is set to 1/64 in manual.  Triggers my FL-600R just fine, but I always get some light from the on camera flash hitting my subject...

Thanks