Snowden only needs a German passport.
There was a person with a German passport years ago, he was wrongly held in Guantanamo for a while ... against all international rights. Even after they concluded, that there is no evidence against him, they still kept him for some years.
See here: http://en.wikipedia.org/wiki/Murat_Kurnaz
Do you think, only because Snowden has got some German looking waste-paper, the NSA will stop hunting him down?
Dream on!
But most people understand by asylum, that he comes to Germany.
I hope, you don't want to unembarrass Putin ;)