Sam and I tried to use relevance_rails for a new server. The provisioning was initiated from an EC2 instance. sshing in always fails from the relevance_rails API (which wraps Fog). We tried sshing directly with the Fog API and that fails too. sshing from the command line works fine.
Our guess is that specifying the key to Fog 1.3.1 (locked by Rails 3.2.6) fails somewhere.