On my lan I have a camera that is programmed to send http post data to my laptop ip: 8088 which is running fiddler.
Can fiddler display this incoming data? So far I only seem to see be able to see requests originating on my laptop but I need to see this incoming data.
Your camera is a separate device which is most likely having its own IP address and thus it needs to be reconfigured to use the proxy set by Fiddler. Whether this is possible depends on what are the capabilities of the camera but it should be similar to how an Android device is being setup (see article here)
The camera does allow setting a proxy. I have turned on the proxy in fidder (laptop_ip:8866) and set the camera to use laptop_ip:8866 without credentials, but the camera will still try to send the data (via the proxy) to a endpoint that has no server running to receive the data?
I would say that the best approach is to check the camera instructions on how to modify and use the network setting and the endpoints. Is the camera using secure connection (HTTPS)? If so then it would also need to install the user trust certificate that Fiddler Everywhere issues (as for Android device).