That makes sense. Do you know if the description you gave is publicly available on gist/github/etc?
On the other hand… good news! I figured it out that for you.
Here is the endpoint that you’re looking for:
to enable motion detection:
http://your_camera_ip:port/cgi-bin/event.cgi?msubmenu=motion&action=apply&device=1
to disable it:
http://your_camera_ip:port/cgi-bin/event.cgi?msubmenu=motion&action=apply&device=0
to enable audio detection
http://your_camera_ip:port/cgi-bin/event.cgi?msubmenu=audio&action=apply&device=1
turn it off:
http://your_camera_ip:port/cgi-bin/event.cgi?msubmenu=audio&action=apply&device=0
You should see “OK” string after each successful call.
Please verify if that works by going to the camera interface and see if the state changed by refreshing the page after you’ve changed the state. Try that in your browser of course and if that works we will go from there.