Wix Toolset: Create Sql Login

I'm working on an installer based on wix 3.9 which deploys a database along with other needed files. The installer must also add a Login to the SQL Server with sysadmin rights.

I have followed this thread with this code but I think that a local user is being created and definitely not an Login on my sql instance and unfortunately due to permissions I can't even access the CP to check for that. Any ideas would be helpful since I can't find any documentation on the issue.

<util:Group Id="Users"
        Name ="Benutzer"
        Domain="[ComputerName]" />
 <Component Id ="CreateUserAccount"
       Guid="AEE91491-99FA-40A9-AB47-1E9FC2DDEF2A"
       Directory="TARGETDIR">
<util:User Id ="SQLUser"
           Name="[DBUSER_PROP]"
           Password="[DBPW_PROP]"
           UpdateIfExists="no"
           CreateUser="yes"
           PasswordNeverExpires="yes"
           PasswordExpired="no"
           RemoveOnUninstall="no">
    <util:GroupRef Id ="Users" />
</util:User>