Standalone Named User is, if I understand correctly, essentially locked to the username. If you have different user names on different computers then as it will consider them to be different users, as otherwise the "name" control would be meaningless. (Otherwise if you gave the key to me, I could just say "Yup, I'm Graham!" no matter that my username has nothing to do with "Graham".)
The licenses that allow different usernames on different computers to access under the same license are the Network Floating License, especially with a GROUP option configured to restrict them to a subset of potential users.