It is hard to say whether or not the SpaceX secret Zuma mission was a success or a failure because of the secretive nature of the mission. Viewers watching the launch from the livestream could not see the entire thing. They did not broadcast the separation of the nose cone or the deployment of the satellite.
There are rumors that part of the satellite fell back towards earth and burned up in the atmosphere and other rumors that the satellite is lost in space. These appear to just be rumors though and SpaceX is probably happy the exist to keep the attention off the real mission, which they say was a complete success.