The thing with long coax runs is signal loss. With modern RG6 75-ohm TV coax, half the signal power is lost for every 50' of cable.

Dunno what the specs are on whatever coax is being considered here, but it might not work out as planned, especially for two-way WIFI. It's often easy to boost transmit power to compensate for long coax runs, but that doesn't help with the other direction: reception.