I tried to see if I could get this to not ask for a user, but was unsuccessful. I created a new authentication profile and listed it as "none", then applied it to SSH authentication. This still gives you the "login as" prompt, but after that, it goes straight into the CLI. Even if this worked, it really would not be recommended, as the security of the switch would not be that great. for security reasons, It is very common to see Telnet and HTTP disabled, while leaving HTTPS and SSH enabled.
I am not very familiar with C#, but would it be possible to use SendKey to automate the login prompt?
I have also sent you a direct message requesting the service tag of the unit. This is just to help ensure I have the correct product information.