If you own a Wahoo KICKR18 or KICKR Core, Wahoo released an important firmware update in late 2019 that enabled in-built cadence to be broadcast over ANT+ and Bluetooth connections.
To access this feature, you will need to download the Wahoo Fitness app and update your trainer's firmware to the latest version.
This is particularly helpful for Apple TV users, as it means you can now get around the two device limit and record power, heart rate and cadence in FulGaz. You may need to un-pair your devices from FulGaz and pair them again for this change to be picked up by the app.
Once you have updated your firmware, you will no longer need a separate cadence sensor.