Oh you would be very surprised what that little "without limitation" lets them do. trust me. And everyone here agreed to it.
So tell me. If their wizzy's name to "Daffodil" what would you do about it? Sue them? Do you really think a judge would even listen to such a case especially when PWI has a pretty much all-encompassing ToS agreement? Do you think you have any recourse at all when they ban your account with no reasons given to you?
In the past 7 years hundreds of people have had their accounts shut down and not a one of them can do anything about it. And I am sure some of those accounts have had $1000 or more USD paid into them - without a single penny refunded. If these guys can do that, they can change your name on you if they feel it offends. It is not your decision whether they change your name on you. It is theirs. It is their system, their Rules, and as long as you agree to be bound by them they can do anything involving your accounts that they want within those rules "without limitation".
In your case all it would take is several people complaining that they are offended by your character's name and *poof!* you become "Daffodil".