I am using gazebo classic, so I am actually starting typhoon_h480 ( Gazebo Classic Vehicles | PX4 Guide (main) ) and that model does work with QGroundControl ( both video and photo ), but if I try the code I added in the original post, I get the TIMEOUT error.
I think I kind of found out what is happening. The video is just broadcasted on UPD port 5600 and you can use OpenCV to save it ( How to use the SITL gazebo camera without ROS? - PX4 Autopilot - Discussion Forum for PX4, Pixhawk, QGroundControl, MAVSDK, MAVLink ), but it’s not actually available through MAVSDK.