If by "Panoramic" you are referring to their Technicolor CGM4141 DOCSIS 3.1, then yes, you are out of luck.
According to Cox, it IS NOT compatible with ANY MoCA device - adapter or extender.
I had to return mine and bought an Arris/Surfboard SBG8300 DOCSIS 3.1 Dual Band. I use it along with the Cox 'free" phone eMTA modem. I save rental fees every month and I use a MoCA ECB6200 adapter at the gateway and a few WCB6200Q extenders around the house.
Works perfectly, first time ever I get 940 Mbps via ethernet anywhere I want...