You're encountering basically what I've seen myself when trying to use any of these P2P services. Most of them don't work at all, and those that do seem to work

You're encountering basically what I've seen myself when trying to use any of these P2P services. Most of them don't work at all, and those that do seem to work too slowly to transfer a file of any reasonable size, even on the same WiFi. I have no problems with any other transfers, including torrents, which all run at full speed. But WebRTC stuff just never works for whatever reason.