Could "using passwords" be PR-speak for the su command?
"Snowden persuaded other NSA workers to give up passwords - sources"
So if the intelligence community is lying about how he got access, it is an extremely stupid lie that makes them look like idiots. If they're telling the truth, then it clearly makes the case that their operation is a humongous liability and should be shut down. Either way that explanation/story is bad for the NSA.