Actually this is not in the API - it is in the Wowza Player get started page.
You give the url for playing an .flv with a sub-directory as:
…//[wowza-ip-address]:1935/vod/definst/flv:myVideos/sample.mp4/playlist.m3u8
Do you mean:
…//[wowza-ip-address]:1935/vod/definst/flv:myVideos/sample.flv/playlist.m3u8
Should the .mp4 at the end be.flv?