Picture 6 looks like you've got some burned up stuff. Top of frame, Center and Left of center, looks like your thumb is pointing at a serious issue.
The board which is dangling loose should be mounted to the bottom of the camera holder.
Hope you didn't trade much, they cost $50-70 bucks new.
I wouldn't connect that to my bird, for fear it will short something out.
It looks like a CNC gimbal to me. I THINK the power and ground connect to a couple of the pins shown in Pic 5.
There is a helpful google link in my signature, use the instructions... middle of the page, not the top. Look around, there's lots of threads and pics which might help.
Welcome to the show pitdawg.
Good first post, nice clear pics, good explanation.
Keep it up and you can get what you want quickly here.
What kinda bird have you got? You might want to focus your questions in that forum.