This is what I did. I had to contact UO to detach the account from my main UO account. Then I made an email address and a UO account for that account. Then I attached the account to that UO Account. Then I gave them all the info. Then they can go in and do the same.... Remove it from that UO account and attach it to their own, or just change all the info on the UO account and email account and use that.
It seems like a lot of steps, but it's just time consuming and make sure you write all the new information down as you go along.