I have created an app to control your BlueROV2 with iPad. It replaces QGroundControl.
You can connect via USB Ethernet (Apple dongle) or Wireless if you connect to Fathom-X to router.
It supports bluetooth game controllers or you can use on-screen virtual joysticks.
The app has free trial so you can test it with your setup.
Your feedback would be more than welcome
App Store link: