ROV controlled by Playstation 4 controller

For our high school ROV team, we plan to try and be able to control it by using a Playstation 4 controller using this USB shield(http://www.circuitsathome.com/products-page/arduino-shields/usb-host-shield-2-0-for-arduino-assembled) and this library to go along with it (https://github.com/felis/USB_Host_Shield_2.0). As it so happens, to communicate from the surface of the pool to the ROV, we use an Ethernet connection so we use an ethernet shield on the ROV as well. I am fairly new to this, one of the newer members of the team. As far as I know, you can only put one shield on each Arduino. If I am wrong here, if someone could help me with placing both of them on, please let me know. Otherwise,

I see another option here. Would it be possible to have one Arduino with the USB shield on it to take input from the PS4 controller and then send it to the other Arduino with the ethernet shield on it which would then send it down to the ROV to the various motor drivers and servos as such?

Thanks for any advice possible.

Hi,

See THIS: for an example of stacking multiple Arduino shields.

?? Does the ROV stay connected to the Ethernet cable?

Yes, the ROV will stay connected to the ethernet cable by means of a waterproof tether.