Your feed file is syntactically incorrect. It looks like you tried to format an mrss feed as a JSON feed. Direct publisher requires either an mrss feed or a JSON feed. Please see the feed file spec for either mrss or JSON.
FREE Windows desktop software for converting Direct Publisher channels to SceneGraph (SDK), for creating BIF (Trick Play) files, Roku (MRSS, JSON) feed files, and FireTV feed files @ GitHub/rrirower.