These are messages regarding Wowza (edge) to a RTSP client. Did you test RTMP playback from this edge?
Great distance between origin and edge can be a problem.
To reduce network overhead, you might packetize on the edge instead of the standard configuration. Take out the packetizers from the origin Application.xml /LiveStreamPacketizers, and change the edge Application.xml /LiveStreamPacketizers from the repeater packetizers to the regular packetizers.
You're right, the jitter buffer does not apply to re-streaming rtmp. But you might re-stream RTSP in the edge from the origin and use it to look at packet loss. Follow the IP camera instructions where the origin application is the source