So it would be simpler for me to turn the one Asus in the living room to ap mode and the virgin router back to modem mode and disable WiFi. As the Virgin media TV box needs a coaxThat might cause problems depending on the particular MoCA adapters you're using. We'll see. But you must only plug the living room MoCA adapter into the Asus router's LAN port (because the VM Hub is in modem mode).
The alternative would be to change the VM Hub back to router mode (with Wi-Fi disabled) and put the Asus in the living room into AP mode. Then it wouldn't matter whether the MoCA adapter was plugged into the Hub or the Asus.