How to control payload system through FUTABA RC; S1000 + 2 RC FUTABA T10J + 2 R3008SB

Hi guys, I have DJI S1000 with two T10J Futaba transmitters and two Futaba R3008SB receivers, I would like to add payload drop system, something like that:

Professional Payload Drop Release servo Fishing Drone Plane DJI Phantom MAVIC | eBay

I’m new in RC world and I don’t know much about it.
Can I connect this payload system with my drone and control it through radio connection system? If so how to do it?

I have two futaba receiver (see the picture ) and I’m wondering to which of them I should connect payload system? I’m not sure but the 1st one looks like it’s connected to Gimbal so I assume it will be controlled through transmitter designed to manipulate camera, almost all channel are used, only channel 3 and 8/SB left. Second transmitter is only connected to A2 flight controller and all channels looks like are available, this one I assume is responsible for drone flight?

Does anyone could give me advice what would be the best?

Thank you,

Magda