The system won't allow you to create a new account from a computer where you already have an established account. Best bet is to help the person while they use their personal computer.
Absolutely there is no issue from ECCIE side to create a new account, the issue is from the user side. You need to explain or put down on what kind of error you are getting (not just for this issue alone)...the more info you give the better the solution/help is going to receive. Always use a different network (not necessarily a different computer within same network)
Yes, for sure you can ask websupport team to create an account, but once the account is created (by web team) she needs to use a different network to logon.