[sudo-users] Sudo Question

[Todd C. Miller]

Sudo uses the process's real uid to determine which account to
authenticate as.  Since all the accounts actually map to the "test"
user, that is what sudo will use to authenticate.  There's really
no safe way for sudo to tell the user's identity other than looking
up the uid.  Environment variables won't do since the user can set
those to any value he/she wishes.  This is not a problem for things
like login or ssh since the user name is specified as part of the
login process.

I don't see a way to do what you want with sudo.

 - todd