Trance, what up!!!
Actually, check this out. I found a forum post yesterday saying that you can retrieve a lost account even if you don't have the last credit card number OR the cd keys. I started the process to get my Mills account back yesterday.
Basically, call up POL and tell them that you are not able to access your account. They will ask for the first/last 4 digits of your card number.... when it does not work they will feed you some BS about how they can't help you. Ask to speak to a manager. (Note: When I asked, the guy said "my manager is going to tell you the same thing, do you still want to speak with him?". Insist to talk to a manager.) He put me on hold for about 5 minutes and when he came back he said, "Ok, there is a way to get your account back".
Basically, this is how it works. If you can verify your name and birthdate (which I assume they cannot change)... they will send a file to your email. This file contains some paperwork that you have to print out and take and get notarized. Basically, you go into a place and have to prove that you are the person listed on the piece of paper. (via drivers license, I think) Once notarized, you send it back to POL in the mail. Once they get it, they will send you an email telling you to contact them. Then you simply call them up and get your password to your old account =D
Right now, I am still waiting to get the email with the forms. The place that I found this, the guy said he spent 45 minutes arguing with them before they offered this process. But IMO, its worth it. Mills has like 200 days of playtime, its a shame to start all over.
However, if for some reason it dosn't work. I am almost 31 on my warrior on the new account :P