If the confirmation expired, you are able to resend the email, if you have the confirmation email that allows you to trade. However, you should be logging in with your Pox Nora In Game Username. For example, if your SOE login was SomeoneAwesome But in Game, your PoxNora name was KatFish You should be logging in with username KatFish.
The link in the email confirmation for transferring your account doesn't matter. If you have gone through the transfer process and received the email that means the account has been transferred. To log in you need to use the password you put in and confirmed during the transfer process and the your username which is the name that you go by wile in game.
