.....
Someone else will have to comment about using the H520 ST16S as the second controller when flying the TH missions. I would have to "refresh my memory" on that one (which in this case means I don't have a clue). ....... It would likely take some firmware swapping shenanigans to get the original ST16 APP co-installed and easily available on an H520 ST16S. And then I'm not even sure if it would bind to the H520 drone.
Your best hope here is if someone has already done it and can provide some real information.
Some update. I've been playing.
It actually took very little shenanigans to load the ST16 Flight Mode on an ST16S normally set up for H520. However, actually starting it is currently very inconvenient. The problem is the H520 "DataPilot" APP is set to start by default, and I could not find a way to disable the default. To be clear, I can clear the default in settings, but it comes right back. To compound the inconvenience, neither the Typhoon H "FlightMode" App nor the "Launcher" App show up in the Pad menu.
Soooo...... You have to start the controller, go to the "PAD", uninstall the H520 APP and the H520 "Updater" APP and restart the controller every time you want to use the ST16S as the Camera controller on a Typhoon H Mission. Which means you have to reinstall the H520 APP when you get ready to use the ST16S to fly an H520. And there will be more to that story. On this first try, the Typhoon H FlightMode is stuck in the ST16S craw, and starts by default. The H520 "DataPilot" can be manually started, but It is another level of inconvienience. It does not seem to be running.
I'm not much of an Android guy.
Maybe someone who knows what they are doing with Android can take a look at this to see if there is a way to get "Launcher" to start by default, or at least get either "Launcher" or "Typhoon H FlightMode" to show up on the Pad screen. And disable the "Launce by Default" feature for both FlightMode and DataPilot.
With all that said, the system at least seems to work while sitting on the back porch. It was a Typhoon H drone with CGo3+ camera. The normal ST16 was used as the "Pilot" controller. The ST16S was used for the "Camera" controller. Camera and drone bound with no issue. Motors started. Flight modes changed in response to the switch, camera position moved around in response to the controls. But that is about all I did.