theymos verified alia in /r/GirlsGoneBitcoin, so she had a kind of contact with him.
I think she probably just sent him a PM.
He has also written somewhere that he changes the username in some cases. But there must be a valid reason.Of course in must have a valid reason, cases like changes of essential information specially name changes might be subjected to a background check. To avoid abuse and being used as an advantage to trick others.
Yes creating new account is much better and multiple account is allow but you do not used those accounts for personal gain like bitcoin farming.