There are two ways to get stream from Wowza
1) RTSP
If you publish RTMP stream to Wowza server
Code:
rtmp://wowzahost:1935/live/stream1
It is generally reachable as
Code:
rtsp://wowzahost:1935/live/stream1
So you can just play this RTSP URL on WCS server. WCS will pull the stream by RTSP.
2) RTMP push
You can push existing RTMP stream to WCS-server.
Please checkout Wowza docs how to implement this.
We have also implemented another way - RTMP pulling (I believe you ask about pulling).
However it is currently unavailable in the stable branch of WCS server.
We plan to release this branch in a month.