Think there's strong evidence their whistleblower protections are lacking. Think it's clear the NSA is trying desperately to damage control the situation. While it's possible Snowden attempted to go through the proper channels (and I'd love to see evidence of this), the documents linked in this article only show him testing the waters.
The fact Snowden doesn't want to respond is a pretty good sign this isn't a slam dunk for the anti-spying contingent.
"[Snowden] believes the NSA is still playing games with selective releases, and [he] therefore chooses not to participate in this effort," Wizner said. "He doesn't trust that the intelligence community will operate in good faith."