Herelink 2nd radio and video stream

Dear all,

i’m trying to connect 2 herelink(controller unit) and i’ve got it, it’s easy following the instruction but i can’t setup the buttons of the second controller unit(slave) and let them pass throught the first one. There is a way to program the buttons as we can do with the joystick and the scroll wheel of the second radio? I need to use the second controller to command the payload but the joystick and the scroll wheel ar not enough. Would that be possible if i pair also the second herelink with the airunit? now the two controllers are under the same network so they can see each other.
The second question is: can i stream the video from the first controller to the second controller in manner that in the first controller i can see camera1 and on the second controller i can see camera2?
I hade a lot of reading about that but i can’t reach the solution.
I would like to read and have all the info about how to fully use the second controller connected with the first one, i can’t really find the documentation that fully explain that.

Thanks in advance to all of you.