Quad Cortex and Mission Engineering SP1-L6

I recently bought a Quad Cortex and it seems that my Mission Engineering SP1-L6 expression pedal is not working properly with it. This pedal works perfectly fine with a Line 6 HX Stomp.

I have tried two known-good TRS cables and also a TRS to TS-TS cable with the pedal. The Quad Cortex will recognize the toe switch, but the sweep of the pedal is completely ignored.

Is the SP1-L6 compatible with the Quad Cortex?

Thanks.

Edit** I got a reply from Mission Engineering saying that the L6 version is not compatible with the Quad Cortex.