Flash control disabled on Nikon Z7 when attempting to use external flash

I have a Nikon Z7 and the following rented equipment:

• Nikon SB-910 flash unit
• Phottix Odin II Receiver for Nikon
• Phottix Odin II Flash Trigger for Nikon

The on-camera setup is working great, it’s my first time using a speedlight and I’m delighted with the results (using TTL). The off-camera is giving me trouble from the very first step. I’ve attached, locked and opened all the devices, disabled Silent Photography, enabled Fill Flash and set the shooting type to Single Frame. Regardless, I can’t seem to configure the Radio communication between the trigger and receiver, as the Flash control submenu appears disabled and it shows "This option is not available at current settings or in the camera’s current state" when I try to click it.

What can I do to enable it? Is there a chance that the trigger and receiver are not compatible with my camera? Thanks!