One issue unexplored in the article: was Uber under a document preservation order related to the litigation when it (allegedly) used Wickr to communicate with Ergo about the investigation? If so... I don't think the court will take kindly to either "the chat app ate my homework" or "no really, we agreed to us Wickr and exchanged screen names, and then stopped emailing, but I swear we never actually used it" as defenses.