I am not sure if this is the best place for this info, but thought since it is needed to manually configure and add cameras to the server, this might be a good place to start.
I have a Windows free program called Synesis ONVIF Device Manager, URL is https://synesis.ru/ you will need to see if Chrome and Google translate can translate for you. I found it / got it at SurceForge URL: ONVIF Device Manager download | SourceForge.net
This tool was very helpful in helping me figure out the video stream settings / or path to manually set in setting up a Chinese camera on the DVR. Go check it out at SourceForge. At this time I see the auto discover searches on port 80, in my case the ONVIF is listening on port 8999 so the auto discover can not identify the settings. But with this utility and al little trial and error at settings, you can get enough info from the camera to figure out how to set the camera to the DVR manually.