What Mr. Higgins said. You're going to, at some point, need command-line access to the server, which appears to be hosted by Amazon. That means among other things you'll need certain credentials to get in ...
But more short-term, whoever disabled your predecessor's account presumably has access to create accounts, because that's how it's set up. Unless your predecessor disabled his own account ...
If that's the case, you can try to go the route Mr. Higgins suggested in the second email that just arrived. If not, this *might* work:
Connect to box with SSH, then type this:
sudo -u postgres psql postgres
\connect panda